Enriched terephthalic acid composition

ABSTRACT

A process is provided for producing an enriched carboxylic acid compositions produced by contacting composition comprising a carboxylic acid with an enrichment feed in an enrichment zone to form an enriched carboxylic acid composition. This invention also relates to a process and the resulting compositions for removing catalyst from a carboxylic acid composition to produce a post catalyst removal composition.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 11/365,652,entitled “An Enriched Terephthalic Acid Composition” filed on Mar. 1,2006, which claims priority to U.S. Provisional Application Ser.60/682,765, filed May 19, 2005, the disclosures of which areincorporated herein by reference in their entirety.

FIELD OF INVENTION

This invention relates to a process and resulting enriched carboxylicacid compositions produced by contacting a carboxylic acid compositionwith an enrichment feed in an enrichment zone to form an enrichedcarboxylic acid composition. This invention also relates to a processand the resulting compositions for removing catalyst from a cooledcarboxylic acid composition.

BACKGROUND OF THE INVENTION

Terephthalic acid is commercially produced by oxidation of paraxylene inthe presence of at least one catalyst, such as, for example, Co, Mn, andBr catalyst and a solvent, typically acetic acid. Terephthalic acid istypically made in a manner to remove impurities formed as a result ofthe oxidation of paraxylene.

Terephthalic acid (TPA) is an intermediate in the production ofcondensation polymers and copolymers especially polyesters andco-polyesters for plastics, fibers, films, coatings, containers, andother articles. Of particular commercial importance is poly(ethyleneterephthalate), referred to as PET, a polyester of TPA and ethyleneglycol (EG), as well as related copolyesters. Commercial processes forthe manufacture of TPA are often based on the multi-valent transitionmetal catalyzed oxidation of p-xylene, generally with a bromide promoterin an acetic acid solvent. Due to the limited solubility of TPA inacetic acid under practical oxidation conditions, a slurry ofcrystalline agglomerate containing primarily TPA is usually formed inthe oxidation reactor. Typically, the TPA oxidizer slurry is withdrawnfrom the reactor, and TPA solids are separated from the oxidizer motherliquor using conventional solid-liquid separation techniques. Theoxidizer mother liquor stream, which contains most of the catalyst andpromoter used in the process, is recycled to the oxidation reactor. Inaddition to the catalyst and promoter, the oxidizer mother liquor streamalso contains dissolved TPA and many by-products, impurities, and othercompounds. These other compounds, oxidation by-products and impuritiesarise partially from compounds present in minor amounts in the p-xylenefeed stream. Other compounds and oxidation by-products arise due to theincomplete oxidation of p-xylene resulting in partially oxidizedproducts. Still other compounds and oxidation by-products result fromcompeting side reactions formed as a result of the oxidation of p-xyleneto terephthalic acid. Patents disclosing the production of terephthalicacid such as U.S. Pat. No. 4,158,738 and U.S. Pat. No. 3,996,271 arehereby incorporated by reference in their entirety to the extent thatthey do not contradict statements herein.

Many of the compounds in the oxidizer mother liquor stream that arerecycled are relatively inert to further oxidation, but are not inert tofurther reaction including decomposition and conversion to othercompounds. Such compounds include, for example, isophthalic acid (IPA),benzoic acid, and phthalic acid. Compounds in the oxidizer mother liquorstream, which may undergo further oxidation are also present, such as,for example in the case of oxidation of p-xylene (also known as1,4-dimethylbenzene), compounds such as 4-carboxybenzaldehyde, p-toluicacid, p-tolualdehyde and terephthaldehyde. Compounds that are relativelyinert to oxidation and are not otherwise removed from the process tendto accumulate in the oxidizer mother liquor stream upon recycle.

Conventionally, crude terephthalic acid (CTA) is purified either byconversion to a dimethyl ester or by dissolution in water withsubsequent hydrogenation over standard hydrogenation catalysts. Morerecently, secondary oxidative treatments instead of hydrogenation havebeen used to produce polymer-grade TPA. It is desirable to minimize theconcentration of impurities in the mother liquor and thereby facilitatesubsequent purification of TPA. In some cases, it is not possible toproduce a purified, polymer-grade TPA unless some means for removingimpurities from the oxidizer mother liquor stream is utilized.

One technique for impurity removal commonly used in the chemicalprocessing industry is to draw out or “purge” some portion of the motherliquor stream as a recycle stream. Typically, the purge stream is simplydisposed of or, if economically justified, subjected to varioustreatments to remove undesired impurities while recovering valuablecomponents. One example of this purge process is U.S. Pat. No. 4,939,297herein incorporated by reference in its entirety to the extent that itdoes not contradict statements herein.

The purification of CTA to produce purified terephthalic acid (PTA)increases the manufacturing cost of the PTA. It is desirable to maximizethe concentration of by-products, impurities, and other compounds in theterephthalic acid to the extent that the terephthalic acid remainsuseful, especially in making poly(ethylene terephthalate) (PET) polymerand articles therefrom, such as, film, containers, and fiber.

One example of utility is the improved yield in a carboxylic acidprocess, particularly a terephthalic acid process. Another utility ofthis invention is the flexibility of controlling the destination ofspecific compounds in the process. For example, a portion of specificcompounds can be retained on the product in a catalyst removal zone, andor enriched in the product in the enrichment zones such that they go outwith the product stream, or are allowed to exit the process. Yet anotherutility is the process allows the option of placing compounds on theproduct stream that are not in the TPA process. Another utility is theoption of adding a comonomer, to the TPA product stream, for example,IPA, can be added.

SUMMARY OF THE INVENTION

In a first embodiment of this invention, a terephthalic acid compositionis provided comprising:

-   -   (1) terephthalic acid in an amount greater than 50 percent by        weight;    -   (2) (a) 4-carboxybenzaldehyde in an amount ranging from 1 ppm to        1000 ppm; or        -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            1000 ppm; or both (2) (a) and (2) (b); and    -   (3) at least two of the following:        -   (a) isophthalic acid in an amount ranging from 50 ppm to 49            wt %;        -   (b) trimellitic acid in an amount ranging from 140 ppm to            1000 ppm;        -   (c) 4,4′-dicarboxybiphenyl is in an amount ranging from 25            ppm to 49 wt %;        -   (d) phthalic acid is in an amount ranging from 20 ppm to 49            wt %;        -   (e) 4-hydroxybenzoic acid is in an amount ranging from 3 ppm            to 1000 ppm;        -   (f) 4-hydroxymethylbenzoic acid is in an amount ranging from            40 ppm to 49 wt %; and        -   (g) benzoic acid in an amount ranging from 60 ppm to 1000            ppm.

In another embodiment of this invention, a terephthalic acid compositionis provided comprising:

-   -   (1) terephthalic acid in an amount greater than 50 percent by        weight;    -   (2) (a) 4-carboxybenzaldehyde in an amount ranging from 1 ppm to        1000 ppm; or        -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            1000 ppm; or both (2) (a) and (2) (b); and    -   (3) at least three of the following:        -   (a) isophthalic acid in an amount ranging from ranging from            50 ppm to 49 wt %;        -   (b) trimellitic acid in an amount ranging from 140 ppm to            1000 ppm;        -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 25 ppm            to 49 wt %;        -   (d) phthalic acid in an amount ranging from 20 ppm to 49 wt            %;        -   (e) 4-hydroxybenzoic acid in an amount ranging from 3 ppm to            1000 ppm;        -   (f) 4-hydroxymethylbenzoic acid in an amount ranging from 40            ppm to 49 wt %; and        -   (g) benzoic acid in an amount ranging from 60 ppm to 1000            ppm.

In another embodiment of this invention, a terephthalic acid compositionis provided comprising:

-   -   (1) terephthalic acid in an amount greater than 50 percent by        weight;    -   (2) (a) 4-carboxybenzaldehyde in an amount ranging from 1 ppm to        1000 ppm; or        -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            1000 ppm; or both (2) (a) and (2) (b); and    -   (3) at least two of the following:        -   (a) isophthalic acid in an amount of at least 50 ppm;        -   (b) trimellitic acid ranging from 140 ppm to 1000 ppm; and        -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 25 ppm            to 49 wt %;

In another embodiment of this invention, a terephthalic acid compositionis provided comprising:

-   -   (1) terephthalic acid in an amount greater than 50 percent by        weight;    -   (2) (a) 4-carboxybenzaldehyde in an amount ranging from 1 ppm to        1000 ppm; or        -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            1000 ppm; or both (a) and (b); and    -   (3) all of the following:        -   (a) isophthalic acid in an amount at least 50 ppm;        -   (b) trimellitic acid ranging from 140 ppm to 1000 ppm;        -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 25 ppm            to 49 wt %.

In another embodiment of this invention, a terephthalic acid compositionis provided comprising:

-   -   (1) terephthalic acid in an amount greater than 50 percent by        weight;    -   (2) (a) 4-carboxybenzaldehyde in an amount ranging from 1 ppm to        1000 ppm; or        -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            1000 ppm; or both (a) and (b); and    -   (3) at least five of the following:        -   (a) isophthalic acid in an amount ranging from 50 ppm to 49            wt %;        -   (b) trimellitic acid in an amount ranging from 140 ppm to            1000 ppm;        -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 25 ppm            to 49 wt %;        -   (d) phthalic acid in an amount ranging from 20 ppm to 49 wt            %;        -   (e) 4-hydroxybenzoic acid in an amount ranging from 3 ppm to            1000 ppm;        -   (f) 4-hydroxymethylbenzoic acid in an amount ranging from 40            ppm to 49 wt %; and        -   (g) benzoic acid in an amount ranging from 60 ppm to 1000            ppm.

In another embodiment of this invention, a terephthalic acid compositionis provided comprising:

-   -   (1) terephthalic acid in an amount greater than 50 percent by        weight;    -   (2) (a) 4-carboxybenzaldehyde in an amount ranging from 1 ppm to        1000 ppm; or        -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            1000 ppm; or both (a) and (b); and    -   (3) all of the following:        -   (a) isophthalic acid in an amount ranging from 50 ppm to 49            wt %;        -   (b) trimellitic acid in an amount ranging from 140 ppm to            1000 ppm;        -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 25 ppm            to 49 wt %;        -   (d) phthalic acid is in an amount ranging from 20 ppm to 49            wt %;        -   (e) 4-hydroxybenzoic acid in an amount ranging from 3 ppm to            1000 ppm;        -   (f) 4-hydroxymethylbenzoic acid in an amount ranging from 40            ppm to 49 wt %; and        -   (g) benzoic acid in an amount ranging from 60 ppm to 1000            ppm.

These embodiments, and other embodiments, will become more apparent toothers with ordinary skill in the art after reading this disclosure.

BRIEF DESCRIPTION OF THE DRAWING

FIGS. 1A & B illustrate an embodiment of the invention where a driedcarboxylic acid composition 280 is produced.

FIG. 2 illustrates various embodiments of the invention wherein multipleliquid displacement zones 40 can be used.

FIG. 3 illustrates an embodiment of the invention wherein a crystallizedslurry composition 160 can be produced by multiple different processes.

FIG. 4 illustrates an embodiment of the invention wherein the crudecarboxylic acid composition or a slurry composition can be produced bymultiple different processes.

FIG. 5 illustrates an embodiment of the invention wherein a postcatalyst removal composition 200 is produced from a carboxylic acidcomposition 214 in a catalyst removal zone 180.

FIG. 6 illustrates an embodiment of the invention wherein both acatalyst removal zone 180 and an enrichment zone 210 are utilized toproduce an enriched composition 240 from a cooled carboxylic acidcomposition 170.

FIG. 7 illustrates an embodiment of the invention wherein an enrichedcomposition 240 is produced from a post catalyst removal composition 200in an enrichment zone 210.

FIG. 8 illustrates an embodiment of the invention showing multipleenrichment feed 220 points.

FIG. 9 illustrates various embodiments of the invention wherein acarboxylic acid composition 214 and/or a crystallized slurry composition160 are enriched.

FIG. 10 illustrates various embodiments of the invention wherein acarboxylic acid composition 214 is enriched in an extended enrichmentzone 213.

FIG. 11 illustrates various embodiments of the invention wherein theenrichment zone 210 and the catalyst removal zone 180 can be combinedinto at least one combined catalyst removal/enrichment zone 181 or atleast one device that accomplishes both functions.

FIGS. 12, 13, 14 and 15 Illustrates an embodiment of the inventionshowing multiple enrichment feeds 220 in a given process.

FIG. 16 illustrates an embodiment of the invention wherein an enrichedcomposition 240 is sent directly to an esterification reaction zone 610.

FIG. 17 illustrates an embodiment of the invention wherein a water wetcake composition 246 is sent directly to an esterification reactor zone610.

FIG. 18 illustrates an embodiment of the invention where an aromaticfeedstock 10 is utilized to produce a post catalyst removal composition200.

FIG. 19 illustrates an embodiment of the invention wherein an aromaticfeedstock 10 is utilized to produce an enriched composition 240.

FIGS. 20 A&B illustrates an embodiment of the invention wherein thecatalyst removal zone 180 is optional, and the enrichment zone 210 isrequired.

DETAILED DESCRIPTION OF THE INVENTION

The present invention may be understood more readily by reference to thefollowing detailed description of preferred embodiments of the inventionand the Examples included herein and to the Figures and their previousand following description.

Before the present compounds, compositions, articles, devices, and/ormethods are disclosed and described, it is to be understood that thisinvention is not limited to specific synthetic methods, specificprocesses, or to particular apparatuses, as such may, of course, vary.It is also to be understood that the terminology used herein is for thepurpose of describing particular embodiments only and is not intended tobe limiting.

In this specification and in the claims, which follow, reference will bemade to a number of terms which shall be defined to have the followingmeanings:

As used in the specification and the appended claims, the singular forms“a,” “an” and “the” include plural referents unless the context clearlydictates otherwise. Thus, for example, reference to a catalyst removalzone includes one or more catalyst removal zones.

Ranges may be expressed herein as from “about” one particular value,and/or to “about” another particular value. When such a range isexpressed, another embodiment includes from the one particular valueand/or to the other particular value. Similarly, when values areexpressed as approximations, by use of the antecedent “about,” it willbe understood that the particular value forms another embodiment. Itwill be further understood that the endpoints of each of the ranges aresignificant both in relation to the other endpoint, and independently ofthe other endpoint.

“Optional” or “optionally” means that the subsequently described eventor circumstance may or may not occur, and that the description includesinstances where said event or circumstance occurs and instances where itdoes not. For example, the phrase “optionally heated” means that thematerial may or may not be heated and that such phrase includes bothheated and unheated processes. Notwithstanding that the numerical rangesand parameters setting forth the broad scope of the invention areapproximations, the numerical values set forth in the specific examplesare reported as precisely as possible. Any numerical value, however,inherently contains certain errors necessarily resulting from thestandard deviation found in their respective testing measurements.

The ranges stated in this disclosure and the claims are intended toinclude the entire range specifically and not just the endpoint(s). Forexample, a range stated to be 0 to 10 is intended to disclose all wholenumbers between 0 and 10 such as, for example 1, 2, 3, 4, etc., allfractional numbers between 0 and 10, for example 1.5, 2.3, 4.57, 6.113,etc., and the endpoints 0 and 10. Also, a range associated with chemicalsubstituent groups such as, for example, “C₁ to C₅ hydrocarbons”, isintended to specifically include and disclose C₁ and C₅ hydrocarbons aswell as C₂, C₃, and C₄ hydrocarbons.

In an embodiment of the invention, a post catalyst removal composition200 is optionally contacted with an enrichment feed 220 in an enrichmentzone 210. A slurry composition 70 or crystallized slurry composition 160or cooled carboxylic acid composition 170 or crude carboxylic acidcomposition 30 can be made in any conventional process known in the artfor producing a carboxylic acid composition. The slurry composition 70or crystallized slurry composition 160 or cooled carboxylic acidcomposition 170 or crude carboxylic acid composition 30 is thensubsequently used to produce a dried carboxylic acid composition 280 oran enriched composition 240 or a dewatered cake composition 260. Forexample, one method of making a post catalyst removal composition 200 isprovided in FIGS. 1A & B.

Step (a) in FIG. 1A comprises oxidizing an aromatic feedstock 10 in aprimary oxidation zone 20 to form a crude carboxylic acid composition30. The aromatic feedstock 10 comprises at least one oxidizablecompound, at least one solvent, and at least one catalyst.

One embodiment of the present invention concerns the liquid-phasepartial oxidation of an oxidizable compound. Such oxidation ispreferably carried out in the liquid phase of a multi-phase reactionmedium contained in an agitated reactor or reactors. Suitable agitatedreactors include, for example, bubble-agitated reactors (e.g., bubblecolumn reactors) and mechanically agitated reactors (e.g., continuousstirred tank reactors). The liquid-phase oxidation is preferably carriedout in a bubble column reactor.

As used herein, the term “bubble column reactor” shall denote a reactorfor facilitating chemical reactions in a multi-phase reaction medium,wherein agitation of the reaction medium is provided primarily by theupward movement of gas bubbles through the reaction medium. As usedherein, the term “agitation” shall denote work dissipated into thereaction medium causing fluid flow and/or mixing. As used herein, theterms “majority”, “primarily”, and “predominantly” shall mean more than50 percent.

The oxidizable compound present in the aromatic feed stock 10 preferablycomprises at least one hydrocarbyl group. More preferably, theoxidizable compound is an aromatic compound. Still more preferably, theoxidizable compound is an aromatic compound with at least one attachedhydrocarbyl group or at least one attached substituted hydrocarbyl groupor at least one attached heteroatom or at least one attached carboxylicacid function (—COOH). Even more preferably, the oxidizable compound isan aromatic compound with at least one attached hydrocarbyl group or atleast one attached substituted hydrocarbyl group with each attachedgroup comprising from 1 to 5 carbon atoms. Yet still more preferably,the oxidizable compound is an aromatic compound having exactly twoattached groups with each attached group comprising exactly one carbonatom and consisting of methyl groups and/or substituted methyl groupsand/or at most one carboxylic acid group. Even still more preferably,the oxidizable compound is para-xylene, meta-xylene, para-tolualdehyde,meta-tolualdehyde, para-toluic acid, meta-toluic acid, and/oracetaldehyde. Most preferably, the oxidizable compound is para-xylene.

A “hydrocarbyl group”, as defined herein, is at least one carbon atomthat is bonded only to hydrogen atoms or to other carbon atoms. A“substituted hydrocarbyl group”, as defined herein, is at least onecarbon atom bonded to at least one heteroatom and to at least onehydrogen atom. “Heteroatoms”, as defined herein, are all atoms otherthan carbon and hydrogen atoms. “Aromatic compounds”, as defined herein,comprise an aromatic ring, preferably having at least 6 carbon atoms,even more preferably having only carbon atoms as part of the ring.Suitable examples of such aromatic rings include, but are not limitedto, benzene, biphenyl, terphenyl, naphthalene, and other carbon-basedfused aromatic rings.

Suitable examples of the oxidizable compound include aliphatichydrocarbons (e.g., alkanes, branched alkanes, cyclic alkanes, aliphaticalkenes, branched alkenes, and cyclic alkenes); aliphatic aldehydes(e.g., acetaldehyde, propionaldehyde, isobutyraldehyde, andn-butyraldehyde); aliphatic alcohols (e.g., ethanol, isopropanol,n-propanol, n-butanol, and isobutanol); aliphatic ketones (e.g.,dimethyl ketone, ethyl methyl ketone, diethyl ketone, and isopropylmethyl ketone); aliphatic esters (e.g., methyl formate, methyl acetate,ethyl acetate); aliphatic peroxides, peracids, and hydroperoxides (e.g.,t-butyl hydroperoxide, peracetic acid, and di-t-butyl hydroperoxide);aliphatic compounds with groups that are combinations of the abovealiphatic species plus other heteroatoms (e.g., aliphatic compoundscomprising one or more molecular segments of hydrocarbons, aldehydes,alcohols, ketones, esters, peroxides, peracids, and/or hydroperoxides incombination with sodium, bromine, cobalt, manganese, and zirconium);various benzene rings, naphthalene rings, biphenyls, terphenyls, andother aromatic groups with one or more attached hydrocarbyl groups(e.g., toluene, ethylbenzene, isopropylbenzene, n-propylbenzene,neopentylbenzene, para-xylene, meta-xylene, ortho-xylene, all isomers oftrimethylbenzenes, all isomers of tetramethylbenzenes,pentamethylbenzene, hexamethylbenzene, all isomers ofethyl-methylbenzenes, all isomers of diethylbenzenes, all isomers ofethyl-dimethylbenzenes, all isomers of dimethylnaphthalenes, all isomersof ethyl-methylnaphthalenes, all isomers of diethylnaphthalenes, allisomers of dimethylbiphenyls, all isomers of ethyl-methylbiphenyls, andall isomers of diethylbiphenyls, stilbene and with one or more attachedhydrocarbyl groups, fluorene and with one or more attached hydrocarbylgroups, anthracene and with one or more attached hydrocarbyl groups, anddiphenylethane and with one or more attached hydrocarbyl groups);various benzene rings, naphthalene rings, biphenyls, terphenyls, andother aromatic groups with one or more attached hydrocarbyl groupsand/or one or more attached heteroatoms, which may connect to otheratoms or groups of atoms (e.g., phenol, all isomers of methylphenols,all isomers of dimethylphenols, all isomers of naphthols, benzyl methylether, all isomers of bromophenols, bromobenzene, all isomers ofbromotoluenes including alpha-bromotoluene, dibromobenzene, cobaltnaphthenate, and all isomers of bromobiphenyls); various benzene rings,naphthalene rings, biphenyls, terphenyls, and other aromatic groups withone or more attached hydrocarbyl groups and/or one or more attachedheteroatoms and/or one or more attached substituted hydrocarbyl groups(e.g., benzaldehyde, all isomers of bromobenzaldehydes, all isomers ofbrominated tolualdehydes including all isomers ofalpha-bromotolualdehydes, all isomers of hydroxybenzaldehydes, allisomers of bromo-hydroxybenzaldehydes, all isomers of benzenedicarboxaldehydes, all isomers of benzene tricarboxaldehydes,para-tolualdehyde, meta-tolualdehyde, ortho-tolualdehyde, all isomers oftoluene dicarboxaldehydes, all isomers of toluene tricarboxaldehydes,all isomers of toluene tetracarboxaldehydes, all isomers ofdimethylbenzene dicarboxaldehydes, all isomers of dimethylbenzenetricarboxaldehydes, all isomers of dimethylbenzene tetracarboxaldehydes,all isomers of trimethylbenzene tricarboxaldehydes, all isomers ofethyltolualdehydes, all isomers of trimethylbenzene dicarboxaldehydes,tetramethyl benzene dicarboxaldehyde, hydroxymethyl-benzene, all isomersof hydroxymethyl-toluenes, all isomers of hydroxymethyl-bromotoluenes,all isomers of hydroxymethyl-tolualdehydes, all isomers ofhydroxymethyl-bromotolualdehydes, benzyl hydroperoxide, benzoylhydroperoxide, all isomers of tolyl methyl-hydroperoxides, and allisomers of methylphenol methyl-hydroperoxides); various benzene rings,naphthalenes rings, biphenyls, terphenyls, and other aromatic groupswith one or more attached selected groups, selected groups meaninghydrocarbyl groups and/or attached heteroatoms and/or substitutedhydrocarbyl groups and/or carboxylic acid groups and/or peroxy acidgroups (e.g., benzoic acid, para-toluic acid, meta-toluic acid,ortho-toluic acid, all isomers of ethylbenzoic acids, all isomers ofpropylbenzoic acids, all isomers of butylbenzoic acids, all isomers ofpentylbenzoic acids, all isomers of dimethylbenzoic acids, all isomersof ethylmethylbenzoic acids, all isomers of trimethylbenzoic acids, allisomers of tetramethylbenzoic acids, pentamethylbenzoic acid, allisomers of diethylbenzoic acids, all isomers of benzene dicarboxylicacids, all isomers of benzene tricarboxylic acids, all isomers ofmethylbenzene dicarboxylic acids, all isomers of dimethylbenzenedicarboxylic acids, all isomers of methylbenzene tricarboxylic acids,all isomers of bromobenzoic acids, all isomers of dibromobenzoic acids,all isomers of bromotoluic acids including alpha-bromotoluic acids,tolyl acetic acid, all isomers of hydroxybenzoic acid isomers, allisomers of hydroxymethyl-benzoic acids, all isomers of hydroxytoluicacids, all isomers of hydroxymethyl-toluic acids, all isomers ofhydroxymethyl-benzene dicarboxylic acids, all isomers ofhydroxybromobenzoic acids, all isomers of hydroxybromotoluic acids, allisomers of hydroxymethyl-bromobenzoic acids, all isomers of carboxybenzaldehydes, all isomers of dicarboxy benzaldehydes, perbenzoic acid,all isomers of hydroperoxymethyl-benzoic acids, all isomers ofhydroperoxymethyl-hydroxybenzoic acid isomers, all isomers ofhydroperoxycarbonyl-benzoic acids, all isomers ofhydroperoxycarbonyl-toluenes, all isomers of methylbiphenyl carboxylicacids, all isomers of dimethylbiphenyl carboxylic acids, all isomers ofmethylbiphenyl dicarboxylic acids, all isomers of biphenyl tricarboxylicacids, all isomers of stilbene with one or more attached selectedgroups, all isomers of fluorenone with one or more attached selectedgroups, all isomers of naphthalene with one or more attached selectedgroups, benzil, all isomers of benzil with one or more attached selectedgroups, benzophenone, all isomers of benzophenone with one or moreattached selected groups, anthraquinone, all isomers of anthraquinonewith one or more attached selected groups, all isomers of diphenylethanewith one or more attached selected groups, benzocoumarin, and allisomers of benzocoumarin with one or more attached selected groups).

It should be understood that the oxidizable compound present in theliquid-phase feed may comprise a combination of two or more differentoxidizable chemicals. These two or more different chemical materials canbe fed co-mingled in the aromatic feedstock 10 or may be fed separatelyin multiple feed streams. For example, an aromatic feed stock comprisingpara-xylene, meta-xylene, para-tolualdehyde, para-toluic acid, andacetaldehyde may be fed to the reactor via a single inlet or multipleseparate inlets.

The solvent present in the aromatic feed stock 10 preferably comprisesan acid component and a water component. In an embodiment of theinvention, the solvent is preferably present in the aromatic feedstock10 at a concentration in the range of from about 60 to about 98 weightpercent, more preferably in the range of from about 80 to about 96weight percent, and most preferably in the range of from 85 to 94 weightpercent. The acid component of the solvent is preferably an organic lowmolecular weight monocarboxylic acid having 1-6 carbon atoms, morepreferably 2 carbon atoms. Most preferably, the acid component of thesolvent is acetic acid. Preferably, the acid component makes up at leastabout 75 weight percent of the solvent, more preferably at least about80 weight percent of the solvent, and most preferably 85 to 98 weightpercent of the solvent, with the balance being water.

Suitable solvents include, but are not limited to, aliphaticmono-carboxylic acids, preferably containing 2 to 6 carbon atoms, orbenzoic acid and mixtures thereof and mixtures of these compounds withwater.

The catalyst system present in the aromatic feed stock 10 is preferablya homogeneous, liquid-phase catalyst system capable of promotingoxidation (including partial oxidation) of the oxidizable compound. Morepreferably, the catalyst system comprises at least one multi-valenttransition metal. Still more preferably, the multi-valent transitionmetal comprises cobalt. Even more preferably, the catalyst systemcomprises cobalt and bromine. Most preferably, the catalyst systemcomprises cobalt, bromine, and manganese.

When cobalt is present in the catalyst system, it is preferred for theamount of cobalt present in the aromatic feedstock 10 to be such thatthe concentration of cobalt in the liquid phase of the reaction mediumin the primary oxidation zone 20 is maintained in the range of fromabout 300 to about 6,000 parts per million by weight (ppmw), morepreferably in the range of from about 700 to about 4,200 ppmw, and mostpreferably in the range of from 1,200 to 3,000 ppmw. When bromine ispresent in the catalyst system, it is preferred for the amount ofbromine present in the aromatic feedstock to be such that theconcentration of bromine in the liquid phase of the reaction medium ismaintained in the range of from about 300 to about 5,000 ppmw, morepreferably in the range of from about 600 to about 4,000 ppmw, and mostpreferably in the range of from 900 to 3,000 ppmw. When manganese ispresent in the catalyst system, it is preferred for the amount ofmanganese present in the aromatic feedstock 10 to be such that theconcentration of manganese in the liquid phase of the reaction medium ismaintained in the range of from about 20 to about 1,000 ppmw, morepreferably in the range of from about 40 to about 500 ppmw, mostpreferably in the range of from 50 to 200 ppmw.

The concentrations of the cobalt, bromine, and/or manganese in theliquid phase of the reaction medium, provided above, are expressed on atime-averaged and volume-averaged basis. As used herein, the term“time-averaged” shall denote an average of at least 10 measurementstaken over a continuous 100 second period of time. As used herein, theterm “volume-averaged” shall denote an average of at least 10measurements taken at uniform 3-dimensional spacings throughout acertain volume.

The weight ratio of cobalt to bromine (Co:Br) in the catalyst systemintroduced into the primary oxidation zone 20 is preferably in the rangeof from about 0.25:1 to about 4:1, more preferably in the range of fromabout 0.5:1 to about 3:1, and most preferably in the range of from0.75:1 to 2:1. The weight ratio of cobalt to manganese (Co:Mn) in thecatalyst system introduced into the primary oxidation zone 20 ispreferably in the range of from about 0.3:1 to about 40:1, morepreferably in the range of from about 5:1 to about 30:1, and mostpreferably in the range of from 10:1 to 25:1.

The aromatic feedstock 10 introduced into the primary oxidation zone 20can include small quantities of compounds such as, for example,meta-xylene, ortho-xylene, toluene, ethylbenzene, 4-carboxybenzaldehyde(4-CBA), benzoic acid, para-toluic acid, para-toluic aldehyde, alphabromo para-toluic acid, isophthalic acid, phthalic acid, trimelliticacid, polyaromatics, and/or suspended particulates.

Step (b) optionally comprises removing at least a portion of oxidationbyproducts from a crude carboxylic acid composition 30 in a liquiddisplacement zone 40 to form a slurry composition 70.

A crude carboxylic acid composition 30 comprises at least one carboxylicacid, at least one catalyst, at least one solvent, and at least oneoxidation byproduct at least a portion of which are withdrawn via line60. Oxidation byproducts typically comprise at least one or more of thefollowing classes of compounds and their isomers: carboxylic acids,aldehydes, hydroxyaldehydes, carboxyaldehydes, ketones, alcohols, andhydrocarbons. In the case of oxidation of p-xylene, oxidationby-products typically comprise at least one of the following compounds:4-carboxybenzaldehyde, p-toluic acid, p-tolualdehyde, isophthalic acid,phthalic acid, benzoic acid, trimellitic acid, 4,4′-dicarboxybiphenyl,2,6- and 2,7-dicarboxyfluorenone, 2,6-dicarboxyanthraquinone,4,4′-dicarboxybenzophenone, 4,4′-dicarboxybiphenyl, and a-bromo-p-toluicacid. The solvent typically comprises acetic acid, but can be anysolvent that has been previously mentioned.

The crude carboxylic acid composition 30 is produced by oxidizing in aprimary oxidation zone 20 an aromatic feed stock 10. In one embodiment,the aromatic feedstock 10 comprises paraxylene. The primary oxidationzone 20 comprises at least one oxidation reactor. The crude carboxylicacid composition 30 comprises at least one carboxylic acid.

In an embodiment of the invention, the oxidation reactor can be operatedat temperatures between about 110° C. to about 200° C.; another range isbetween about 140° C. to about 170° C. Typically, the oxidizablecompound in the aromatic feedstock 10 is paraxylene, and the carboxylicacid produced is terephthalic acid. In one embodiment of the invention,the primary oxidation zone 20 comprises a bubble column.

Carboxylic acids include aromatic carboxylic acids produced viacontrolled oxidation of an organic substrate or any carboxylic acidproduced by the oxidation of oxidizable compounds previously mentioned.Such aromatic carboxylic acids include compounds with at least onecarboxylic acid group attached to a carbon atom that is part of anaromatic ring, preferably having at least 6 carbon atoms, even morepreferably having only carbon atoms. Suitable examples of such aromaticrings include, but are not limited to, benzene, biphenyl, terphenyl,naphthalene, and other carbon-based fused aromatic rings. Examples ofsuitable carboxylic acids include, but are not limited to, terephthalicacid, benzoic acid, p-toluic, phthalic acid, isophthalic acid,trimellitic acid, naphthalene dicarboxylic acid, and2,5-diphenyl-terephthalic acid.

Crude terephthalic acid slurry is conventionally produced via the liquidphase oxidation of paraxylene in the presence of suitable oxidationcatalyst. In another embodiment of the invention, suitable catalystsinclude, but are not limited to, cobalt, manganese and brominecompounds, which are soluble in the selected solvent.

The crude carboxylic acid composition in conduit 30 is optionally fed toa liquid displacement zone 40 capable of removing a portion of theliquid contained in the crude carboxylic acid composition 30 to producethe slurry composition in conduit 70. In embodiments of the invention, aportion means at least 5% by weight of the liquid is removed. In anotherembodiment of the invention, a portion means at least 10% by weight ofthe liquid is removed. In another embodiment of the invention, a portionmeans at least 15% by weight of the liquid is removed. In anotherembodiment of the invention, a portion means at least 25% by weight ofthe liquid is removed. In another embodiment of the invention, a portionmeans at least 35% by weight of the liquid is removed. In anotherembodiment of the invention, a portion means at least 45% by weight ofthe liquid is removed. In another embodiment of the invention, a portionmeans at least 55% by weight of the liquid is removed. In anotherembodiment of the invention, a portion means at least 65% by weight ofthe liquid is removed. In another embodiment of the invention, a portionmeans at least 75% by weight of the liquid is removed. In anotherembodiment of the invention, a portion means at least 85% by weight ofthe liquid is removed. In another embodiment of the invention, a portioncan mean any part up to and including the whole by weight of the liquidis removed.

The removal of a portion of the liquid to produce a slurry compositionin conduit 70 can be accomplished by any means known in the art.Typically, the liquid displacement zone 40 comprises a solid-liquidseparator that is selected from the group consisting of a decantercentrifuge, disk stack centrifuge, vacuum belt filter, rotary vacuumfilter, rotary pressure filter, perforated basket centrifuge and thelike. The crude carboxylic acid composition in conduit 30 is fed to theliquid displacement zone 40 comprising at least one solid-liquidseparator. In an embodiment of the invention, the solid-liquid separatorcan be operated at temperatures between about 5° C. to about 200° C. Inyet another range, the solid-liquid separator can be operated from about90° C. to about 170° C. In yet another range, the solid-liquid separatorcan be operated from about 140° C. to about 170° C. The solid-liquidseparator can be operated at pressures up to 200 psig. In yet anotherrange the solid liquid separator can be operated at pressures betweenabout 30 psig to about 200 psig. The solid-liquid separator in theliquid displacement zone 40 may be operated in continuous or batch mode,although it will be appreciated that for commercial processes, thecontinuous mode is preferred.

A portion of the oxidation byproducts are displaced from the liquiddisplacement zone 40 in a mother liquor and withdrawn via line 60. Inone embodiment of the invention, additional solvent is fed to the liquiddisplacement zone 40 via line 50 to reslurry the crude carboxylic acidcomposition 30 and form a slurry composition 70. The mother liquor 60 iswithdrawn from liquid displacement zone 40 via line 60 and comprises asolvent, typically acetic acid, catalyst, and at least one oxidationbyproduct(s). The mother liquor in line 60 may either be sent to aprocess for separating impurities from oxidation solvent via lines notshown or recycled to the catalyst system via lines not shown. Onetechnique for impurity removal from the mother liquor 60 commonly usedin the chemical processing industry is to draw out or “purge” someportion of the recycle stream. Typically, the purge stream is simplydisposed of, or if economically justified, subjected to varioustreatments to remove undesired impurities while recovering valuablecomponents. Examples of impurity removal processes include U.S. Pat. No.4,939,297 and U.S. Pat. No. 4,356,319, herein incorporated by referenceto the extent that they do not contradict statements made herein.

In embodiments of the present invention a process is described that canallow for the controlled partitioning of at least one selected compound,by-product or impurity among the filtration mother liquor, wash feed,and terephthalic acid wet cake while achieving recovery of theoxidization catalyst and oxidation reaction solvent or medium.

Also in embodiments of this invention, the purge process can besignificantly reduced or eliminated by the enrichment of a post catalystremoval composition 200 with selected compounds. The enrichment processresults in these compounds being carried out with the enrichedcomposition 240 or the dried carboxylic acid composition 280, thereforegreatly reducing or eliminating a purge process. The enrichment can bepreceded by a catalyst removal process.

It should be pointed out that the liquid displacement zone 40 isoptional and also can be located in multiple locations in the process asshown in FIG. 2 by the dashed lines. In another embodiment of theinvention, there are more than one liquid displacement zone(s) 40 suchas, for example, between the primary oxidation zone 20 and stagedoxidation zone 80, and another liquid displacement zone 40 can belocated either after the staged oxidation zone 80 or after thecrystallization zone 120. There could be three liquid displacement zones40 as shown in FIG. 2 or any combination as shown in FIG. 2.

Step (c) comprises optionally oxidizing the slurry composition 70 or acrude carboxylic acid composition 30 in a staged oxidation zone 80 toform a staged oxidation composition 110.

In one embodiment of the invention, the slurry composition 70 or a crudecarboxylic acid composition 30 is withdrawn via line 70 to a stagedoxidation zone 80 and can be heated to between about 140° C. to about280° C. Another range is between about 160° C. to about 240° C., anotherrange is between about 170° C. to about 200° C., and further oxidizedwith air fed by line 106 to produce a staged oxidation composition 110.Another range is about 180° C. to about 280° C.

The staged oxidation zone 80 comprises at least one staged oxidationreactor vessel. The slurry composition 70 is fed to the staged oxidationzone 80. The term “staged” means that the oxidation occurs in both theprimary oxidation zone 20 discussed previously as well as in the stagedoxidation zone 80. For example, the staged oxidation zone 80 cancomprise staged oxidation reactor vessels in series.

When the carboxylic acid is terephthalic acid, the staged oxidation zone80 comprises an oxidation reactor that can be heated to between about140° C. to about 280° C. or between about 160° C. to about 240, orbetween about 170° C. to about 200° C., or between about 160° C. toabout 210° C., and further oxidized with air or a source of molecularoxygen fed by line 106 to produce a staged oxidation composition 110. Inan embodiment of the invention, oxidation in the staged oxidation zone80 is at a higher temperature than the oxidation in the primaryoxidation zone 20 to enhance the impurity removal. The staged oxidationzone 80, as well as streams 30 and 70, can be heated directly withsolvent vapor, or steam, or indirectly by any means known in the art.Purification in the staged oxidation zone 80 takes place by a mechanisminvolving recrystallization or crystal growth and oxidation ofimpurities.

Additional air or molecular oxygen may be fed via conduit 106 to thestaged oxidation zone 80 in an amount necessary to oxidize at least aportion of the partially oxidized products, such as,4-carboxybenzaldehyde (4-CBA) and p-toluic acid in the crude carboxylicacid composition 30 or slurry composition 70 to the correspondingcarboxylic acid. Generally, at least 70% by weight of the 4-CBA isconverted to terephthalic acid in the staged oxidation zone 80.Preferably, at least 80% by weight of the 4-CBA is converted toterephthalic acid in the staged oxidation zone 80. Significantconcentrations of 4-carboxybenzaldehyde and p-toluic acid in theterephthalic acid product are particularly detrimental to polymerizationprocesses as they may act as chain terminators during the condensationreaction between terephthalic acid and ethylene glycol in the productionof polyethylene terephthalate (PET).

Impurities in the crude carboxylic acid composition 30 or slurrycomposition 70 go into solution as the terephthalic acid particles aredissolved and re-crystallized in the staged oxidation zone 80. Offgasfrom the staged oxidation zone 80 is withdrawn and can be fed to arecovery system where the solvent is removed from the offgas comprisingvolatile organic compounds (VOCs). VOCs including methyl bromide may betreated, for example, by incineration in a catalytic oxidation unit. Theoffgas may also be processed before the staged oxidation composition 110from the staged oxidation zone 80 is withdrawn via line 110.

Step (d) comprises optionally crystallizing the slurry composition 70 orthe crude carboxylic acid composition 30 or the staged oxidationcomposition 110 in a crystallization zone 120 to form a crystallizedslurry composition 160. Generally, the crystallization zone 120comprises at least one crystallizer. Vapor product from thecrystallization zone 120 can be condensed in at least one condenser andreturned to the crystallization zone 120. Optionally, the liquid fromthe condenser or vapor product from the crystallization zone 120 can berecycled, or it can be withdrawn or sent to an energy recovery device.

In addition, the crystallizer offgas is removed and can be routed to arecovery system where the solvent is removed and crystallizer offgascomprising VOCs may be treated, for example, by incineration in acatalytic oxidation unit.

The staged oxidation composition 110 from the staged oxidation zone 80is withdrawn via line 110 and fed to a crystallization zone 120comprising at least one crystallizer where it is cooled to a temperaturebetween about 110° C. to about 190° C. to form a crystallized slurrycomposition 160, preferably to a temperature between about 140° C. toabout 180° C., and most preferably about 150° C. to about 170° C.

The crystallized slurry composition 160 from the crystallization zone120 is withdrawn via line 160. Typically, the crystallized slurrycomposition 160 is then fed directly to a vessel and cooled to form acooled carboxylic acid composition 170. When the carboxylic acid isterephthalic acid, the cooled carboxylic acid composition 170 is cooledin a vessel to typically a temperature of about 160° C. or less,preferably to about 100° C. or less, before being introduced into aprocess for recovering the terephthalic acid as a dry powder or wetcake.

Step (e) comprises optionally cooling the crystallized slurrycomposition 160 or the staged oxidation composition 110 or the slurrycomposition 70 or the crude carboxylic acid composition 30 in a coolingzone 165 to form a cooled carboxylic acid composition 170.

The crystallized slurry composition 160 or the staged oxidationcomposition 110 or the slurry composition 70 or the crude carboxylicacid composition 30 is fed to a cooling zone 165 and cooled to atemperature ranging from about 5° C. to about 160° C., or about 5° C. toabout 90° C., or about 5° C. to about 195° C. or about 20° C. to about160° C. to form the cooled carboxylic acid composition 170. In anotherembodiment of the invention, the crystallized slurry composition 160 orthe staged oxidation composition 110 or the slurry composition 70 or thecrude carboxylic acid composition 30 is fed to a cooling zone 165 andcooled to a temperature ranging from about 20° C. to about 90° C. toform the cooled carboxylic acid composition 170. In another embodimentof the invention, the crystallized slurry composition 160 or the stagedoxidation composition 110 or the slurry composition 70 or the crudecarboxylic acid composition 30 is fed to a cooling zone 165 and cooledto a temperature ranging from about 20° C. to about 120° C. to form thecooled carboxylic acid composition 170. In another embodiment of theinvention, the crystallized slurry composition 160 or the stagedoxidation composition 110 or the slurry composition 70 or the crudecarboxylic acid composition 30 is fed to a cooling zone 165 and cooledto a temperature ranging from about 10° C. to about 90° C. to form thecooled carboxylic acid composition 170. In another embodiment of theinvention, the crystallized slurry composition 160 or the stagedoxidation composition 110 or the slurry composition 70 or the crudecarboxylic acid composition 30 is fed to a cooling zone 165 and cooledto a temperature ranging from about 20° C. to about 60° C. to form thecooled carboxylic acid composition 170. In another embodiment of theinvention, the crystallized slurry composition 160 or the stagedoxidation composition 110 or the slurry composition 70 or the crudecarboxylic acid composition 30 is fed to a cooling zone 165 and cooledto a temperature ranging from about 20° C. to about 40° C. to form thecooled carboxylic acid composition 170.

In another embodiment of the invention, a portion of the solvent isoptionally removed from the crystallized slurry composition 160 or thestaged oxidation composition 110 or the slurry composition 70 or thecrude carboxylic acid composition 30 via conduit 163 to produce thecooled carboxylic acid composition 170. In one embodiment of theinvention, a portion can mean any part up to and including the whole. Aportion can mean at least 5% by weight of the solvent is removed. Inanother embodiment of the invention, a portion can mean at least 10% byweight of the solvent is removed. In another embodiment of theinvention, a portion can mean at least 25% by weight of the solvent isremoved. In another embodiment of the invention, a portion can mean atleast 50% by weight of the solvent is removed. In another embodiment ofthe invention, a portion can mean at least 75% by weight of the solventis removed. In another embodiment of the invention, a portion can meanat least 85% by weight of the solvent is removed. In another embodimentof the invention, a portion can mean at least 90% by weight of thesolvent is removed from the crystallized slurry composition 160 or thestaged oxidation composition 110 or the slurry composition 70 or thecrude carboxylic acid composition 30.

Solvent removal can be accomplished by any means known in the art. Forexample, the solvent can be removed by evaporation or by flashing andremoving the solvent under vacuum.

In another embodiment of the invention, both cooling and solvent removalare utilized.

Steps (a) through steps (d) and steps (a) through (e) are to illustrateembodiments of the invention in which a cooled carboxylic acidcomposition 170 is produced. In should also be pointed out that theliquid displacement zone 40, the staged oxidation zone 80, and thecrystallization zone 120 were all optional in this embodiment of theinvention. For example, other processes that produce a cooled carboxylicacid composition 170, or a crystallized slurry composition 160, or astaged oxidation composition 110, or a slurry composition 70, or a crudecarboxylic acid composition 30 can be utilized. Such processes aredescribed in U.S. Pat. Nos. 5,877,346; 4,158,738; 5,840,965; 5,877,346;U.S. Pat. No. 5,527,957; and U.S. Pat. No. 5,175,355, all of which areherein incorporated by reference in their entirety to the extent thatthey do not contradict statements made herein. Therefore, as shown inFIG. 3, any process known in the art capable of producing a crystallizedslurry composition 160 can be utilized. In addition, as shown in FIG. 4,any process known in the art capable of producing a crude carboxylicacid composition 30 or a slurry composition 70 can be utilized

Generally, as depicted in FIG. 5, any carboxylic acid composition 214can be used in step (f) provided the carboxylic acid composition orcooled carboxylic acid composition 170 comprises at least one carboxylicacid, at least one solvent and at least one catalyst. The carboxylicacid comprises any carboxylic acid previously disclosed or anycarboxylic acid capable of being produced by the oxidation of theoxidizable compounds previously disclosed. The solvent is typicallyacetic acid, but can be any solvent previously disclosed. The catalystis any catalyst that has been previously disclosed. FIG. 6 shows aprocess that utilizes a cooled carboxylic acid composition 170 in step(f).

Step (f) comprises contacting a cooled carboxylic acid composition 170,or a crystallized slurry composition 160, or a staged oxidationcomposition 110 or a slurry composition 70, or a crude carboxylic acidcomposition 30 with a wash feed 175 and optionally an enrichment feed220 in a catalyst removal zone 180 to form a catalyst rich liquor 185, awash liquor stream 62, an optional depleted enrichment liquor stream230, and a post catalyst removal composition 200.

The cooled carboxylic acid composition 170, or a crystallized slurrycomposition 160, or a staged oxidation composition 110 or a slurrycomposition 70, or a crude carboxylic acid composition 30 is contactedwith a wash feed 175 in the catalyst removal zone 180. In an embodimentof the invention the cooled carboxylic acid composition 170 can be inthe form or a dry powder, wet cake, liquid or gas entrained liquid,solid, slurry, solution or combination thereof.

The wash feed 175 is contacted with the cooled carboxylic acidcomposition 170, or a crystallized slurry composition 160, or a stagedoxidation composition 110 or a slurry composition 70, or a crudecarboxylic acid composition 30 in the catalyst removal zone 180 toremove a portion of the catalyst from the cooled, purified carboxylicacid composition 170 to form the post catalyst removal composition 200.In an embodiment of the invention, the post catalyst removal composition200 comprises a carboxylic acid, solvent, catalyst, and optionally, oneor more compounds selected from the group consisting of isophthalicacid, phthalic acid, trimellitic acid, hydroxymethylbenzoic acidisomers, hydroxybenzoic acid isomers, benzoic acid, and toluic acidisomers. In another embodiment of the invention, the post catalystremoval composition 200 comprises a carboxylic acid, solvent andoptionally one or more compounds selected from the group consisting ofisophthalic acid, phthalic acid, trimellitic acid, benzoic acid,4-hydroxybenzoic acid, 4-hydroxymethyl benzoic acid,4,4′-dicarboxybiphenyl, 2,6-dicarboxyanthraquinone,4,4′-dicarboxystilbene, 2,5,4′-tricarboxybiphenyl,2,5,4′-tricarboxybenzophenone, 4,4′-dicarboxybenzophenone,4,4′-dicarboxybenzil, form-acet-hydroxybenzoic acid,acet-hydroxymethylbenzoic acid, a-bromo-p-toluic acid, bromo-benzoicacid, bromo-acetic acid, p-tolualdehye and terephthaldehyde. In anembodiment of the invention, the post catalyst removal composition 200can be in the form of a dry powder, wet cake, slurry, solution, liquid,gas-entrained liquid or solid. In another embodiment of the inventionthe post catalyst removal composition 200 can comprise any compositionsuitable to produce the dried carboxylic acid composition 280 to bedescribed subsequently.

A portion of the catalyst is removed via the catalyst rich liquor 185and the wash liquor 62 from the cooled carboxylic acid composition 170,or a crystallized slurry composition 160, or a staged oxidationcomposition 110 or a slurry composition 70, or a crude carboxylic acidcomposition 30 to produce the post catalyst removal composition 200having a catalyst concentration of less than 1000 ppm by weight. Thecatalyst rich liquor 185 comprises solvent, catalyst, and an oxidationbyproduct(s). The wash liquor 62 comprises at least one solvent, atleast one catalyst, an at least one oxidation byproduct(s). As usedherein, catalyst can be at least one catalyst previously described inthe catalyst system. In another embodiment of the invention, catalystcan be any catalyst used in an oxidation reaction of an aromaticfeedstock. In another embodiment of the invention, a portion of catalystis removed when the post catalyst removal composition 200 has a catalystconcentration of less than 500 ppm by weight. In another embodiment ofthe invention, a portion is that amount of catalyst that is removed suchthat the post catalyst removal composition 200 has a catalystconcentration of less than 250 ppm by weight. In another embodiment ofthe invention, a portion is that amount of catalyst that is removed suchthat the post catalyst removal composition 200 has a catalystconcentration of less than 75 ppm by weight. Another range is less than50 ppm by weight. In yet other ranges, the catalyst concentration of thepost catalyst removal composition 200 is less than 20 ppm by weight orless than 10 ppm by weight. In yet other ranges, the catalystconcentration is less than 5 ppm by weight or less than 1 ppm by weight.As used herein “catalyst concentration” means the total concentration ofall catalyst in the composition.

The wash feed 175 comprises compositions that are capable of producingthe post catalyst removal composition 200 previously disclosed. In anembodiment of the invention, the wash feed 175 can be in a form of aliquid or a condensable vapor or a solution. In another embodiment ofthe invention, the wash feed 175 is greater than 50% by weight water. Inanother embodiment of the invention, the wash feed 175 is greater than75% by weight water. In another embodiment of the invention, the washfeed 175 is greater than 90% by weight water. In another embodiment ofthe invention, the wash feed 175 is greater than 50% by weight solvent.In another embodiment of the invention, the wash feed 175 is greaterthan 75% by weight solvent. In another embodiment of the invention, thewash feed 175 is greater than 90% by weight solvent. In anotherembodiment of the invention, the wash feed 175 comprises at least onesolvent, and optionally at least one compound selected from the groupconsisting of benzoic acid, isophthalic acid, phthalic acid, trimelliticacid, hydroxybenzoic acid isomers, hydroxymethylbenzoic acid isomers,and p-toluic acid. In another embodiment of the invention the wash feed175 comprises compositions sufficient to produce the dried carboxylicacid composition 280 disclosed subsequently. In another embodiment ofthe invention the wash feed 175 comprises at least one solvent, andoptionally at least one compound selected from the group consisting ofisophthalic acid, phthalic acid, trimellitic acid, hydroxymethylbenzoicacid isomers, hydroxybenzoic acid isomers, benzoic acid, and toluic acidisomers and wherein at least one of the compounds is enriched above theconcentration of the post catalyst removal composition 200. In anotherembodiment of the invention, the wash feed 175 comprises at least onesolvent, and optionally, one or more compounds selected from the groupconsisting of isophthalic acid, phthalic acid, trimellitic acid, benzoicacid, 4-hydroxybenzoic acid, 4-hydroxymethylbenzoic acid,4,4′-dicarboxybiphenyl, 2,6-dicarboxyanthraquinone,4,4′-dicarboxystilbene, 2,5,4′-tricarboxybiphenyl,2,5,4′-tricarboxybenzophenone, 4,4′-dicarboxybenzophenone,4,4′-dicarboxybenzil, form-acet-hydroxybenzoic acid,acet-hydroxymethylbenzoic acid, a-bromo-p-toluic acid, bromo-benzoicacid, bromo-acetic acid, p-tolualdehye and terephthaldehyde.

In an embodiment of the invention the wash feed has a temperatureranging from the freezing point of the solvent to about 90° C., or about5° C. to about 90° C., or about 5° C. to about 195° C., or about 5° C.to about 100° C. or the freezing point of the solvent to about 70° C.,or about 5° C. to about 70° C., or about 30° C. to about 70° C., or thefreezing point of the solvent to about 30° C.

In an embodiment of the invention the wash ratio ranges from about 0.2to about 6.0, or about 0.2 to about 4.0, or about 0.2 to about 1.0, orabout 0.4 to about 1, or about 0.5 to about 2.0, or about 1 to about 3.The “wash ratio” as used herein means the total mass of the wash feed175 divided by the mass of the post catalyst removal composition 200 ona dry solids basis.

The catalyst removal zone 180 comprises at least one solid liquidseparation device capable of contacting the cooled carboxylic acidcomposition 170 or a crystallized slurry composition 160, or a stagedoxidation composition 110 or a slurry composition 70, or a crudecarboxylic acid composition 30 with the wash feed 175 to produce a postcatalyst removal composition 200.

For example, the catalyst removal zone 180 comprises one solid liquidseparation device in which a post catalyst removal composition 200 isgenerated and then washed with a wash solvent. Examples include, but arenot limited to, a rotary vacuum drum filter, a vacuum belt filter, arotary pressure filter, a filter press, and a pressure leaf filter.Solid liquid separation devices, which can generate a cake but do notallow washing, are also useful when combined with a reslurry device.Solid liquid separation devices, such as, a solid bowl centrifuge can beused to generate a cake which can be reslurried with wash solvent in aseparate mixing device to achieve washing by dilution. Washing bydilution often requires multiple stages of cake generation andsubsequent reslurrying operated in a counter current fashion.

Step (g) comprises optionally contacting a post catalyst removalcomposition 200 with a enrichment feed 220 in an enrichment zone 210 toform a depleted enrichment stream 230 and an enriched composition 240;wherein the enriched composition 240 comprises one or more compoundsselected from the group consisting of isophthalic acid, phthalic acid,trimellitic acid, hydroxymethylbenzoic acid isomers, hydroxybenzoic acidisomers, benzoic acid, and toluic acid isomers and wherein at least oneof the compounds is enriched above the concentration of the postcatalyst removal composition 200. In another embodiment of theinvention, the enriched composition 240 comprises one or more compoundsselected from the group consisting of isophthalic acid, phthalic acid,trimellitic acid, benzoic acid, 4-hydroxybenzoic acid,4-hydroxymethylbenzoic acid, 4,4′-dicarboxybiphenyl,2,6-dicarboxyanthraquinone, 4,4′-dicarboxystilbene,2,5,4′-tricarboxybiphenyl, 2,5,4′-tricarboxybenzophenone,4,4′-dicarboxybenzophenone, 4,4′-dicarboxybenzil,form-acet-hydroxybenzoic acid, acet-hydroxymethylbenzoic acid,a-bromo-p-toluic acid, bromo-benzoic acid, bromo-acetic acid,p-tolualdehye and terephthaldehyde.

The term “enriched” means that primary outlet stream leaving anenrichment zone or plurality of enrichment zones, or any zone, or anyconveyance mentioned herein has a greater concentration of any selectedenrichment compound(s) than the primary inlet stream going into anenrichment zone or plurality of enrichment zones, wherein the enrichmentcompound(s) comprises at least one compound or compounds selected fromthe group consisting of terephthalic acid, isophthalic acid, phthalicacid, benzene-tricarboxylic acid isomers, benzoic acid, hydroxybenzoicacid isomers, hydroxymethylbenzoic acid isomers, dicarboxybiphenylisomers, dicarboxystilbene isomers, tricarboxybiphenyl isomers,tricarboxybenzophenone isomers, dicarboxybenzophenone isomers,dicarboxybenzil isomers, form-acet-hydroxybenzoic acid isomers,acet-hydroxymethylbenzoic acid isomers, a-bromo-toluic acid isomers,bromo-benzoic acid, bromo-acetic acid, tolualdehye isomers, andphthaldehyde isomers. In another embodiment of the invention, enrichmentcompounds or the enrichment feed 220 can also include monomers,co-monomers, additives, or any compounds useful for making polyester orany combination thereof. For example, in an embodiment of the inventiondepicted on FIGS. 1 a and 1 b, the primary outlet stream is the enrichedcomposition 240 and the primary inlet stream is the post catalystremoval composition 200. In an embodiment of the invention, shown inFIG. 9, the primary inlet stream is the carboxylic acid composition 214,or the crystallized slurry composition 160, and the primary outletstream is the enriched carboxylic acid stream 280. In an embodiment ofthe invention, depicted in FIG. 10, the primary inlet stream is thecarboxylic acid composition 214, and the primary outlet stream is theenriched carboxylic acid composition 216.

In other embodiments of the invention, the termed “enriched” means thatthe primary outlet stream has a greater concentration of any selectedcompound(s) as described previously by at least 5 ppmw, or at least 10ppmw, or at least 100 ppmw, or at least 1000 ppmw, or at least 5 wt %,or at least 10 wt %, or at least 25 wt %, or at least 30 wt % or atleast 50 wt % than the primary inlet stream, all measured on a dry solidbasis.

The enrichment feed 220 comprises compounds sufficient to enrich atleast one compound selected from the group consisting of terephthalicacid, isophthalic acid, phthalic acid, benzene-tricarboxylic acidisomers, benzoic acid, hydroxybenzoic acid isomers, hydroxymethylbenzoicacid isomers, dicarboxybiphenyl isomers, dicarboxystilbene isomers,tricarboxybiphenyl isomers, tricarboxybenzophenone isomers,dicarboxybenzophenone isomers, dicarboxybenzil isomers,form-acet-hydroxybenzoic acid isomers, acet-hydroxymethylbenzoic acidisomers, a-bromo-toluic acid isomers, bromo-benzoic acid, bromo-aceticacid, tolualdehye isomers, benzyl alcohol isomers, methyl benzyl alcoholisomers, and phthaldehyde isomers. In the another embodiment of theinvention, the enrichment feed 220 can also include monomers,co-monomers, additives, or any compounds useful for making polyester orany combination thereof. In another embodiment of the invention theenrichment compounds or enrichment feed 220 comprises one or morecompounds selected from the group consisting of fluorene isomers,diphenyl methane isomers, diphenyl ethane isomers, and saturatedaromatic isomers. Examples of saturated aromatic isomers include, butare not limited to, cyclohexane carboxylic acid and 1,4-cyclohexanedicarboxylic acid.

In another embodiment of the invention, the enrichment feed 220comprises compounds sufficient to enrich the post catalyst removalcomposition 200 as shown in FIG. 7 such that on a dry solids basis theenriched composition 240 comprises compositions identical to the driedcarboxylic acid composition 280 described subsequently. There are nospecial limitations as far as the conditions of the enrichment feed 220other than it comprises compounds sufficient to enrich the post catalystremoval composition 200 with the enrichment compound(s) specifiedpreviously. For example, the enrichment feed 220 can be, but is notlimited to a cake, powder, solids, wash feed, slurry, solution, paste,or gas entrained solid or liquid.

It should be pointed out that the enrichment feed 220 does notnecessarily need to be introduced into the enrichment zone 210. As shownin FIG. 8, the enrichment feed 220 can be introduced in a number oflocations including, but not limited to, the enrichment zone 210,dewatering zone 250, drying zone 270, and in the polyester processes, ormore specifically PET processes. A variety of polyester processes havebeen developed. Early efforts used reactive distillation as shown inU.S. Pat. No. 2,905,707 and reactive distillation with ethylene glycol(“EG”) vapor as reactants as shown in U.S. Pat. No. 2,829,153 to producePET: both of these patents are herein incorporated by reference to theextent they do not contradict statements made herein. Multiple stirredpots have been disclosed to gain additional control of the reaction asshown in U.S. Pat. No. 4,110,316, herein incorporated by reference tothe extent it does not contradict statement made herein. U.S. Pat. No.3,054,776 discloses the use of lower pressure drops between reactors ina PET process, while U.S. Pat. No. 3,385,881 discloses multiple reactorstages within one reactor shell, both of these patents are hereinincorporated by reference to the extent they do not contradict statementmade herein. These designs were improved to solve problems withentrainment or plugging, heat integration, heat transfer, reaction time,the number of reactors, etc., as described in U.S. Pat. Nos. 3,118,843;3,582,244; 3,600,137; 3,644,096; 3,689,461; 3,819,585; 4,235,844;4,230,818; and 4,289,895; all of which are herein incorporated byreference to the extent that they do not contradict statements madeherein.

In a PET process 400 as shown in FIG. 8, the enrichment feed 220 can beintroduced in the paste tank, esterification reactors, and/or otherlocations in the process. The enrichment feed 220 can be introduced inmultiple locations or at only one location, either at one time orgradually over time.

Raw materials for manufacturing step-growth polymers and copolymers fromterephthalic acid (TPA) include monomers and co-monomers, catalyst(s),and additives. Monomers and co-monomers include, but are not limited to,diamines, diols, and diacids, etc. Important commercial step-growthpolymers which can be made using TPA as a monomer or co-monomer includepolyamides, polyesters, especially poly(ethylene terephthalate) (PET),co-polyamides, co-polyesters, and co-polyester-amides. It can beadvantageous to introduce and achieve intimate mixing of the monomers orco-monomers, catalyst(s) and/or additives with the terephthalic acid, sothat they do not have to be added to the polymerization processseparately from the TPA. A process has been invented that allows for theproduction of terephthalic acid, in the form of powder, paste, wet cake,or slurry, and which is enriched with certain monomers or co-monomers,catalyst(s) and/or additives. This process is achieved with intimatemixing with TPA so as to obviate the need for separate addition of thematerials in the PET manufacturing process.

The following description will be given for PET, but can be extended ina straight-forward manner to other step-growth polymers and copolymersmade using TPA. The manufacture of PET involves the esterification ofterephthalic acid with ethylene glycol, formation of a prepolymer, andpolycondensation to form PET with a molecular weight high enough for theintended subsequent polymer processing and application which can includecoatings, fibers, films, containers, and other articles. Certainmonomers or co-monomers, catalyst(s) and/or additives can also be used.The most common co-monomers, beside ethylene glycol (EG), areisophthalic acid (IPA or PIA) and cyclohexanedimethanol (CHDM). The mostcommon catalysts for PET manufacture are antimony and titanium.Additives useful in the manufacture of PET include, but are not limitedto, phosphorous compounds, dyes, pigment, colorants, reheat agents,polydispersity modifiers, antioxidants and stabilizers (thermal,oxidative, UV, etc.), coupling or chain-extending agents, end-cappingagents, telechelic modifiers, such as, for example metal co-ordinatedsulfo-isophthalic acid, acetaldehyde reducing agents, acetaldehydescavengers, buffers, agents to reduce formation of diethylene glycol(DEG), antistats, slip or anti-block agents, barrier modifiers,nucleators, titanium dioxide and other fillers/opacifiers, anti-foggingagents, optical brighteners, etc. The introduction of such co-monomers,catalyst(s), and/or additives is typically at various points in the PETmanufacturing process separate from the addition of TPA. However, it canbe advantageous to introduce certain additives with the TPA, i.e. priorto the PET manufacturing process, especially co-monomers, such as,isophthalic acid and dyes or colorants which are thermally stable. Thus,co-monomers, catalyst(s), and additives can be introduced and intimatelymixed with the TPA during the TPA manufacturing process rather thanduring the PET manufacturing process. Specific TPA manufacturing stepsin which the intimate introduction of additive(s) can be achievedinclude addition at the solid liquid separation device for isolating theTPA cake, at any drying equipment, at or in any conveyance line orprocess pipeline, and prior to shipping the TPA product in anycontainer. Thus, the TPA product in any form, whether dry solids (withresidual water or acetic acid), wet cake (with some liquid water, ormethanol, or EG, or some other diol or co-monomer, or mixtures), wetpaste (with some liquid water, or methanol, or EG, or some other diol orco-monomer, or mixtures), or slurry (with water, or methanol, or EG, orsome other diol or co-monomer, or mixtures), can be enriched prior touse in PET manufacture

In addition, FIG. 9 depicts that the enrichment feed 220 can beintroduced and enrichment can occur at any point from the crystallizedslurry composition 160 to the dried carboxylic acid composition 280.

Another embodiment of the invention is provided in FIG. 10. Theenrichment process can be conducted on a carboxylic acid composition 214in an extended enrichment zone 213 to produce an enriched carboxylicacid composition 216. The enrichment feed 220 can comprise anycomposition previously or subsequently disclosed. There are nolimitations on the carboxylic acid composition other than the carboxylicacid composition 214 comprises a carboxylic acid, optional solvent, andoptionally a catalyst. In another embodiment of the invention thecarboxylic acid composition can be used to produce the dried carboxylicacid composition 280.

It should also be pointed out that in another embodiment of theinvention, the enrichment zone 210 and the catalyst removal zone 180 canbe combined into one zone comprising at least one device thataccomplishes both functions as shown in FIG. 11.

There are no special limitations for the enrichment feed 220 other thanit has a composition suitable to enrich the post catalyst removalcomposition 200. For example, the enrichment feed 220 can be a solid, awash, a slurry, a paste, solids, solution or gas entrained liquid orsolid. In an embodiment of the invention, the enrichment feed 220comprises compositions capable of making the dried carboxylic acid cakecomposition 280. In another embodiment of the invention, the enrichmentfeed 220 are only solids and are added at one point or throughout theprocess to produce the dried carboxylic acid cake composition 280.

FIGS. 12, 13, 14 and 15 illustrate one embodiment of the inventionshowing how an enrichment feed 220 can be obtained and how theenrichment feed 220 is utilized through the process. In FIGS. 12, 13,14, and 15, the enrichment feed(s) are depicted as stream 220. This isto illustrate that the enrichment feed(s) 220 can be taken from avariety of sources or one source and the enrichment feed(s) can have avariety of different compositions, different physical forms, anddifferent addition points in the process. Also, the enrichment feed 220can be added at one time, intermittently, or gradually throughout theprocess.

FIG. 15 illustrates one embodiment of the invention on how an enrichmentfeed 220 can be obtained. At least a portion of the catalyst rich liquor185 is fed to a cooling and/or concentration zone 300 to generate aconcentrated mother liquor stream 310 and a solvent stream 311.Sufficient solvent removal in the cooling and/or concentration zone 300is achieved such that the concentrated catalyst rich stream 310 can havea % solids ranging from 10% by weight to 45% by weight.

A portion of the concentrated mother liquor stream 310 and an extractionsolvent stream 323 is fed to an extraction zone 320 to generate acatalyst rich stream 324 and a catalyst depleted stream 350. The balanceof the concentrated mother liquor stream 310 and a wash stream 331 isfed to a solid-liquid separation zone (SLS Zone), generating a wet cakestream 340 and wash liquor stream 332, comprising mother liquor and washliquor. The wet cake stream 340 can be used as an enrichment feed 220and a portion of the wet cake stream 340 can be sent to the productfilter or product dryer to enrich the product stream with at least aportion of the contents of the wet cake stream 340. Alternatively, aportion of the wet cake stream 340 and a portion of catalyst depletedstream 350 can be fed to an optional mix zone where the two streams aremixed forming an enrichment feed 220 and a portion of this stream can besent to a product filter or product dryer to enrich the product streamwith at least a portion of the contents of enrichment feed 220.

The extraction zone 320 comprises at least one extractor. The extractionsolvent 323 used in the extractor should be substantiallywater-insoluble to minimize the amount of organic solvent dissolved inthe aqueous fraction. Additionally, the extraction solvent 323 ispreferably an azeotropic agent which serves to assist solvent recoveryfrom the organic extract. Solvents which have proven to be particularlyuseful are C1 to C6 alkyl acetates, particularly n-propyl acetate(n-PA), isopropyl acetate, isobutyl acetate, sec-butyl acetate, ethylacetate and n-butyl acetate, although other water-insoluble organicsolvents having an appropriate density and a sufficiently low boilingpoint may also be used, such as p-xylene. N-propyl acetate and isopropylacetate are particularly preferred due to their relatively low watersolubility, excellent azeotropic behavior, and their ability to removethe remaining acetic acid as well as high-boiling organic impuritiesfrom the aqueous mixture.

The extraction can be effected using solvent ratios from about 1 toabout 4 parts by weight solvent per part of extractor feed depending onthe extractor feed composition. Space velocities of the combined feedsto the extractor generally range from 1 to about 3 hr⁻¹. Although theextraction can be done at ambient temperature and pressure, heating thesolvent and extractor to about 30° C. to about 70° C., or about 40° C.to about 60° C., can be used.

FIGS. 12, 13, and 14 illustrate one embodiment of the invention showinghow an enrichment feed 220 can be utilized throughout the process.Aromatic feed stock 10 comprising reactants and catalyst are fed to theprimary oxidation zone 20 generating a crude carboxylic acid composition30. The crude carboxylic acid composition 30 and a solvent stream 50 arefed to liquid displacement zone 40 to achieve a partial solvent swapexchanging a portion of the oxidation solvent present in stream 30 withpure solvent generating a displaced solvent stream 60 and a slurrycomposition stream 70. The slurry composition 70 and a gas streamcontaining oxygen 106 are fed to a staged oxidation zone 80 to generatea staged oxidation composition 110. The staged oxidation composition 110and a solvent stream 101 are fed to a liquid displacement zone 100 toachieve a partial solvent swap exchanging a portion of the oxidationsolvent present in the staged oxidation composition 110 with puresolvent generating a displaced solvent stream 102 and a post solventswap staged oxidation composition 115. The post solvent swap stagedoxidation composition 115 is fed to a crystallization zone 120generating a crystallized slurry composition Stream 160, an optionalsolvent vapor stream 121, and an optional liquid solvent stream 122. Thecrystallized slurry composition stream 160 and an optional enrichmentfeed 220 is fed to a cooling zone 165 where a cooled carboxylic acidcomposition stream 170 and an optional oxidation solvent stream 163 isgenerated. The cooled carboxylic acid composition 170, a wash feed 175,and an optional enrichment feed 220 are fed to a catalyst removal zone180 to generate a post catalyst removal composition 200, the catalystrich liquor 185, and a wash liquor 62, and a depleted enrichment feed230. The post catalyst removal composition 200, swap solvent stream 201,and an optional enrichment fee 220 are fed to an optional solvent swapzone 205 to generate a swap solvent liquor 202, and post solvent swapcomposition 206. The post solvent swap composition 206 and an enrichmentfeed 220 are fed to an enrichment zone 210 to generate an enrichedcarboxylic acid composition Stream 240 and a depleted enrichment feed230. The enriched composition 240 and an optional enrichment feed 220are fed to an optional dewatering zone 250 to generate a dewateredcarboxylic acid composition 260.

The catalyst removal zone 180, solvent swap zone 205, enrichment zone210, dewatering zone 250, and optionally the drying zone 270 can beachieved in a single solid liquid separation device, preferably acontinuous pressure or vacuum filter, and most preferably a vacuum beltfilter. A continuous pressure drum filter or a rotary vacuum drum filtercan also be used. The dewatered enriched carboxylic acid composition260, and an optional enrichment feed 220 are fed to an optional dryingzone 270 to generate a dry enriched carboxylic acid composition 280 anda solvent vapor stream 275.

In another embodiment of the invention, the enrichment feed 220comprises water in a quantity greater than 50% by weight. In anotherembodiment of the invention, the enrichment feed 220 comprises water ina quantity greater than 75% by weight. In another embodiment of theinvention, the enrichment feed 220 comprises water in a quantity greaterthan 95% by weight. In another embodiment of the invention, theenrichment feed 220 comprises water in a quantity greater than 99% byweight.

In another embodiment of the invention, the post catalyst removalcomposition 200 enters the enrichment zone 210 at a temperature in arange of about 200° C. to the freezing point of the enrichment feed 220.In another embodiment of the invention, the post catalyst removalcomposition 200 enters the enrichment zone 210 at a temperature in arange of about 100° C. to the freezing point of the enrichment feed 220.In another embodiment of the invention, the post catalyst removalcomposition 200 enters the enrichment zone 210 at a temperature in arange of about 200° C. to about 0° C. In another embodiment of theinvention, the post catalyst removal composition 200 enters theenrichment zone 210 at a temperature in a range of about 0° C. to 100°C. Other ranges are less than 100° C. to 20° C.; and 40° C. to less than100° C.

The enrichment zone 210 comprises at least one device sufficient toprovide a sufficient amount of contact time between the enrichment feed220 and the post catalyst removal composition 200 to allow for at leastone compound selected from the group consisting of benzoic acid,isophthalic acid, phthalic acid, trimellitic acid, hydroxybenzoic acidisomers, hydroxymethylbenzoic acid isomers, and toluic acid isomers tobe enriched. In another embodiment of the invention, the enrichment zone210 or extended enrichment zone 213 comprises a device that provides asufficient amount of contact time between the enrichment feed and thepost catalyst removal composition 200 or carboxylic acid composition 214to allow monomers, co-monomers, additives, and other compounds useful inthe production of polyesters to be enriched. In another embodiment ofthe invention, the enrichment zone 210 or extended enrichment zone 213comprises at least one device selected from the group consisting of abelt filter, pressure filter, rotary pressure filter, centrifugescapable of adding solids and or a wash stream such as a perforatedbasket centrifuge, a disk stack centrifuge etc, and the like.

In another embodiment of the invention, the enriched composition 240 ona dry solids basis encompasses all possible combinations of compositionsof the dried carboxylic acid composition 280 described subsequently inthis disclosure. Dry solids basis will be described subsequently in thisdisclosure.

All compositions are measured on a dry solids basis to be describedsubsequently in the disclosure. All measurements and claims in ppm arein ppm by weight on a dry solids basis.

Step (h) comprises optionally dewatering the enriched composition 240 ina dewatering zone 250 to form a dewatered post catalyst removalcomposition 260.

The dewatering can be conducted by any means know in the art. Thedewatering results in the dewatered post catalyst removal composition260 having a moisture content of less than 25% by weight moisture. Othermoisture content ranges are less than 15% by weight moisture or lessthan 10% by weight moisture or less than 5% by weight moisture. In yetanother embodiment of the invention, dewatering can be accomplishedthrough the use of mostly mechanical means for drying and wherein themajority of the drying is not accomplished through evaporation. Majorityas used herein means greater than 50%.

Step (i) comprises filtering and optionally drying the enrichedcomposition 240 or the dewatered post catalyst removal composition 260in a filtration and drying zone 270 to remove a portion of the solventfrom the enriched composition 240 or the dewatered post catalyst removalcomposition 260 to produce the dried carboxylic acid composition 280.

The enriched composition 240 or the dewatered post catalyst removalcomposition 260 is withdrawn from the enrichment zone 210 or thedewatering zone 250 and fed to a filtration and drying zone 270.

In one embodiment of the invention, the filtration cake goes through aninitial solvent removal step, is then rinsed with acid wash to removeresidual catalyst, and then solvent is removed again before being sentto the dryers.

The drying zone 270 comprises at least one dryer and can be accomplishedby any means known in the art that is capable of evaporating at least10% of the volatiles remaining in the filter cake to produce the driedcarboxylic acid composition 280. For example, indirect contact dryersincluding a rotary steam tube dryer, a Single Shaft Porcupine® Processordryer, and a Bepex Solidaire® Processor can be used for the drying toproduce a dried carboxylic acid composition 280. Direct contact dryersincluding a fluid bed dryer and drying in a convey line can be used fordrying to produce a dried carboxylic acid composition 280. In anotherembodiment of the invention, drying can be accomplished in asolid-liquid separation device like a vacuum belt filter or a rotarypressure drum filter by allowing a gas stream to flow through the filtercake thus removing volatiles. In another embodiment of the invention, asolid-liquid separation device can comprise any combination of thefollowing zones: a catalyst removal zone, an enrichment zone, adewatering zone, and a drying zone. A dried carboxylic acid compositioncan be a carboxylic acid composition with less than 5% moisture,preferably less than 2% moisture, and more preferably less than 1%moisture, and even more preferably less than 0.5%, and yet morepreferably less than 0.1%.

In an embodiment of the invention, the dried carboxylic acid composition280 has a b* less than about 9.0. In another embodiment of theinvention, the b* color of the dried carboxylic acid composition 280 isless than about 6.0. In another embodiment of the invention, the b*color of the dried carboxylic acid composition 280 is less than about5.0. In another embodiment of the invention, the b* color of the driedcarboxylic acid composition 280 is less than about 4.0. In anotherembodiment of the invention, the b* color of the dried carboxylic acidcomposition 280 is less than about 3. The b* color is one of thethree-color attributes measured on a spectroscopic reflectance-basedinstrument. A Hunter Ultrascan XE instrument in reflectance mode istypically the measuring device. Positive readings signify the degree ofyellow (or absorbance of blue), while negative readings signify thedegree of blue (or absorbance of yellow).

Compositions Comprising at Least One Carboxylic Acid

I. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and optionally,-   (2) (a) carboxybenzaldehyde (CBA) isomers in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid (TA) isomers in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (i) carboxybenzaldehyde isomers in an amount ranging from 1            ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (ii) toluic acid isomers in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of carboxybenzaldehyde and            toluic acid isomers ranges from 1 ppm to 2000 ppm, 1 ppm to            1000 ppm, or from 1 ppm to 500 ppm, or from 1 ppm to 250            ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least one, or at least two, or at least three, or at least    four, or at least five, or at least six, or at least seven, or at    least eight, or at least nine, or at least ten, or at least eleven,    or at least twelve, or at least thirteen, or at least fourteen, or    at least fifteen, or at least sixteen, or at least seventeen, or at    least eighteen, or at least nineteen, or at least twenty, or all of    the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm or 1000 ppm, or ranging from 150 ppm or 500        ppm;    -   (b) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm;    -   (c) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm;    -   (d) benzene-tricarboxylic acid isomers in an amount of at least        125 ppm, or ranging from 125 ppm to 1000 ppm, or ranging from        150 ppm to 750 ppm, or ranging from 175 ppm to 500 ppm;    -   (e) benzoic acid in an amount of at least 50 ppm, or at least 75        ppm, or at least 100 ppm; or ranging from 50 ppm to 500 ppm, or        ranging from 75 ppm to 400 ppm, or ranging from 100 ppm to 300        ppm;    -   (f) hydroxybenzoic acid isomers in an amount of at least 3 ppm,        at least 5 ppm, or at least 20 ppm, or ranging from 3 ppm to 200        ppm, or ranging from 5 ppm to 175 ppm, or ranging from 20 ppm to        150 ppm;    -   (g) hydroxymethylbenzoic acid isomers in an amount of at least        40 ppm, or at least 80 ppm, or at least 100 ppm, or ranging from        40 ppm to 200 ppm, or ranging from 80 ppm to 180, or ranging        from 100 ppm to 160 ppm;    -   (h) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm;    -   (i) dicarboxystilbene isomers in an amount ranging from greater        than 7 ppm; or greater than 10 ppm;    -   (j) tricarboxybiphenyl isomers in an amount ranging from 8 ppm        to 100 ppm, or ranging from 9 ppm to 50 ppm, or ranging from 10        ppm to 25 ppm;    -   (k) tricarboxybenzophenone isomers in an amount ranging from 5        ppm to 100 ppm, or ranging from 6 ppm to 75 ppm, or ranging from        7 ppm to 60 ppm;    -   (l) dicarboxybenzophenone isomers in an amount ranging from 10        ppm to 150 ppm, or ranging from 12 ppm to 100 ppm, or ranging        from 15 ppm to 75 ppm;    -   (m) dicarboxybenzil isomers in an amount ranging from 1 ppm to        30 ppm, or ranging from 2 ppm to 20 ppm, or ranging from 3 ppm        to 10 ppm;    -   (n) form-acet-hydroxybenzoic acid isomers in an amount ranging        from 1 ppm to 20 ppm, or ranging from 2 ppm to 15 ppm, or        ranging from 3 ppm to 10 ppm;    -   (o) acet-hydroxymethylbenzoic acid isomers in an amount ranging        from 1 ppm to 30 ppm, or ranging from 2 ppm to 20 ppm, or        ranging from 3 ppm to 15 ppm;    -   (p) a-bromo-toluic acid isomers in an amount ranging from 1 ppm        to 100 ppm, or ranging from 2 ppm to 50 ppm, or ranging from 5        ppm to 25 ppm;    -   (q) bromo-benzoic acid in an amount ranging from 5 ppm to 50        ppm, or ranging from 10 ppm to 40 ppm, or ranging from 15 ppm to        35 ppm;    -   (r) bromo-acetic acid in an amount ranging from 1 ppm to 10 ppm;    -   (s) tolualdehye isomers in an amount ranging from 7 ppm to 50        ppm, or ranging from 8 ppm to 25 ppm, or ranging from 9 ppm to        20 ppm;    -   (t) phthaldehyde isomers in an amount ranging from 0.25 ppm to        10 ppm, or ranging from 0.5 ppm to-5 ppm, or ranging from 0.75        ppm to 2 ppm; wherein the compound or compounds selected in (3)        are different than the compound or compounds selected in (1) and        (2);-   and optionally,-   (4) at least one, or at least two, or at least three, or at least    four, or at least five or at least six, or at least seven, or at    least eight, or all of the following:    -   (a) terephthalic acid in an amount of at least 1 ppm, or ranging        from 1 ppm to 5000 ppm, or ranging from 5 ppm to 2500 ppm, or        ranging from 10 ppm to 2000 ppm, or ranging from 15 ppm to 1000        ppm, or ranging from 20 ppm to 500 ppm;    -   (b) isophthalic acid in an amount of at least 1 ppm, or ranging        from 1 ppm to 5000 ppm, or ranging from 5 ppm to 2500 ppm, or        ranging from 10 ppm to 2000 ppm, or ranging from 15 ppm to 1000        ppm, or ranging from 20 ppm to 500 ppm;    -   (c) phthalic acid in an amount of at least 1 ppm, or ranging        from 1 ppm to 3000 ppm, or ranging from 2 ppm to 2000 ppm, or        ranging from 3 ppm to 1000 ppm, or ranging from 4 ppm to 500        ppm;    -   (d) benzene-tricarboxylic acid isomers in an amount of at least        1 ppm, or ranging from 1 ppm to 3000 ppm, or ranging from 5 ppm        to 2000 ppm, or ranging from 10 ppm to 1000 ppm, or ranging from        20 ppm to 500 ppm;    -   (e) benzoic acid in an amount of at least 1 ppm, or ranging from        1 ppm to 3000 ppm, or ranging from 5 ppm to 2000 ppm, or ranging        from 10 ppm to 1000 ppm, or ranging from 20 ppm to 500 ppm;    -   (f) hydroxybenzoic acid isomers in an amount of at least 1 ppm,        or ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to 400        ppm, or ranging from 10 ppm to 200 ppm;    -   (g) hydroxymethylbenzoic acid isomers in an amount of at least 1        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to        400 ppm, or ranging from 10 ppm to 200 ppm;    -   (h) dicarboxybiphenyl isomers in an amount of at least 1 ppm, or        ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to 400 ppm,        or ranging from 10 ppm to 200 ppm;        -   wherein the compound or compounds selected in (4) are            different than the compound or compounds selected in (3).

II. In another embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm; and-   (3) at least two, or at least three, or at least four, or at least    five, or at least six, or seven, or all of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (e) hydroxybenzoic acid isomers ranging from 3 ppm to 200 ppm,        or ranging from 5 ppm to 175 ppm, or ranging from 20 ppm to 150        ppm, or ranging from 3 ppm, or 5 ppm or 20 ppm to 150 ppm, or        175 ppm, or 200 ppm, or 500 ppm, or 1000 ppm;    -   (f) hydroxymethylbenzoic acid isomers in an amount of at least        40 ppm, or at least 80 ppm, or at least 100 ppm, or ranging from        40 ppm to 200 ppm, or ranging from 80 ppm to 180, or ranging        from 100 ppm to 160 ppm, or ranging from 40 ppm, or 80 ppm, or        100 ppm to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1        wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %,        or 49 wt %;    -   (g) benzoic acid ranging from 60 ppm to 500 ppm, or ranging from        75 ppm to 400 ppm, or ranging from 100 ppm to 300 ppm, or        ranging from 60 ppm, or 75 ppm, or 100 ppm to 300 ppm, or 500        ppm, or 1000 ppm.    -   (h) terephthalic acid in an amount of at least 20 ppm, or at        least 50 ppm, or at least 100 ppm, or ranging from 20 ppm to        1000 ppm, or ranging from 50 ppm to 750 ppm, or ranging from 100        ppm to 500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500        ppm, or 750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt        %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or        49 wt %, or ranging from 500 ppm, or 750 ppm, or 1000 ppm to        2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt        %, or 10 wt %, or 25 wt %, or 49 wt %;

III. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or at least three, or at least four, or five, or    all of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (e) benzoic acid ranging from 60 ppm to 500 ppm, or ranging from        75 ppm to 400 ppm, or ranging from 100 ppm to 300 ppm, or        ranging from 60 ppm, or 75 ppm, or 100 ppm to 300 ppm, or 500        ppm, or 1000 ppm.    -   (f) terephthalic acid in an amount of at least 20 ppm, or at        least 50 ppm, or at least 100 ppm, or ranging from 20 ppm to        1000 ppm, or ranging from 50 ppm to 750 ppm, or ranging from 100        ppm to 500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500        ppm, or 750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt        %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or        49 wt %, or ranging from 500 ppm, or 750 ppm, or 1000 ppm to        2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt        %, or 10 wt %, or 25 wt %, or 49 wt %;

IV. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or at least three, or four, or all of the    following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (e) terephthalic acid in an amount of at least 20 ppm, or at        least 50 ppm, or at least 100 ppm, or ranging from 20 ppm to        1000 ppm, or ranging from 50 ppm to 750 ppm, or ranging from 100        ppm to 500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500        ppm, or 750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt        %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or        49 wt %, or ranging from 500 ppm, or 750 ppm, or 1000 ppm to        2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt        %, or 10 wt %, or 25 wt %, or 49 wt %;

V. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight; and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or three, or all of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;

VI. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or all of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

VII. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm; and-   (3) both of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;

VIII. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

IX. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (b) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

X. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or all of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

XI. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;

XII. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) carboxybenzaldehyde isomers (CBA) in an amount ranging from    1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from    1 ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) toluic acid isomers (TA) in an amount ranging from 1 ppm to        1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) carboxybenzaldehyde isomers (CBA) in an amount ranging            from 1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) toluic acid isomers (TA) in an amount ranging from 1 ppm            to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of CBA and TA ranges from 1            ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to 500            ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

XIII. In another embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) carboxylic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight; and-   (2) carboxybenzaldehyde isomers (CBA) in an amount ranging from 1    ppm to 500 ppm, and-   (3) all of the following:    -   (a) phthalic acid isomers in an amount at least 50 ppm, or        ranging from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500        ppm, or ranging from 100 ppm to 1000 ppm, or ranging from 150        ppm to 500 ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm,        or 150 ppm to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or        1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %,        or 49 wt %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt % or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %,        or 25 wt %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) dicarboxybiphenyl isomers in an amount ranging from 20 ppm        to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from        25 ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500        ppm to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %,        or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;        Isophthalic Acid Compositions

I. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) m-toluic acid (m-TA isomers) in an amount ranging from 1 ppm        to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1        ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) m-toluic acid isomers (m-TA) in an amount ranging from 1            ppm to 500 ppm, or ranging from 1 ppm to 250 ppm, or ranging            from 1 ppm to 125 ppm;        -   wherein the total concentration of 3-CBA and m-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm-   and-   (3) at least one, or at least two, or at least three, or at least    four, or at least five, or at least six, or at least seven, or at    least eight, or at least nine, or at least ten, or at least eleven,    or at least twelve, or at least thirteen, or at least fourteen, or    at least fifteen, or at least sixteen, or at least seventeen, or at    least eighteen, or at least nineteen, or all of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm;    -   (b) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm;    -   (c) benzene-tricarboxylic acid isomers in an amount of at least        140 ppm, or ranging from 140 ppm to 1000 ppm, or ranging from        175 ppm to 750 ppm, or ranging from 200 ppm to 500 ppm;    -   (d) benzoic acid in an amount of at least 50 ppm, or at least 75        ppm, or at least 100 ppm; or ranging from 50 ppm to 500 ppm, or        ranging from 75 ppm to 400 ppm, or ranging from 100 ppm to 300        ppm;    -   (e) 3-hydroxybenzoic acid in an amount of at least 3 ppm, at        least 5 ppm, or at least 20 ppm, or ranging from 3 ppm to 200        ppm, or ranging from 5 ppm to 175 ppm, or ranging from 20 ppm to        150 ppm;    -   (f) 3-hydroxymethylbenzoic acid in an amount of at least 40 ppm,        or at least 80 ppm, or at least 100 ppm, or ranging from 40 ppm        to 200 ppm, or ranging from 80 ppm to 180, or ranging from 100        ppm to 160 ppm;    -   (g) 3,3′-dicarboxybiphenyl isomers in an amount ranging from 20        ppm to 150 ppm, or ranging from 25 ppm to 100 ppm, or ranging        from 25 ppm to 75 ppm;    -   (h) dicarboxyanthraquinone isomers in an amount less than 1 ppm,        or less than 0.5 ppm, or less than 0.4 ppm, or less than 0.35        ppm;    -   (i) dicarboxystilbene isomers in an amount ranging from greater        than 7 ppm; or greater than 10 ppm;    -   (j) tricarboxybiphenyl isomers in an amount ranging from 8 ppm        to 100 ppm, or ranging from 9 ppm to 50 ppm, or ranging from 10        ppm to 25 ppm;    -   (k) tricarboxybenzophenone isomers in an amount ranging from 5        ppm to 100 ppm, or ranging from 6 ppm to 75 ppm, or ranging from        7 ppm to 60 ppm;    -   (l) dicarboxybenzophenone isomers in an amount ranging from 10        ppm to 150 ppm, or ranging from 12 ppm to 100 ppm, or ranging        from 15 ppm to 75 ppm;    -   (m) dicarboxybenzil isomers in an amount ranging from 1 ppm to        30 ppm, or ranging from 2 ppm to 20 ppm, or ranging from 3 ppm        to 10 ppm;    -   (n) form-acet-hydroxybenzoic acid isomers in an amount ranging        from 1 ppm to 20 ppm, or ranging from 2 ppm to 15 ppm, or        ranging from 3 ppm to 10 ppm;    -   (o) acet-hydroxymethylbenzoic acid isomers in an amount ranging        from 1 ppm to 30 ppm, or ranging from 2 ppm to 20 ppm, or        ranging from 3 ppm to 15 ppm;    -   (p) a-bromo-m-toluic acid in an amount ranging from 1 ppm to 100        ppm, or ranging from 2 ppm to 50 ppm, or ranging from 5 ppm to        25 ppm;    -   (q) bromo-benzoic acid in an amount ranging from 5 ppm to 50        ppm, or ranging from 10 ppm to 40 ppm, or ranging from 15 ppm to        35 ppm;    -   (r) bromo-acetic acid in an amount ranging from 1 ppm to 10 ppm;    -   (s) m-tolualdehye in an amount ranging from 7 ppm to 50 ppm, or        ranging from 8 ppm to 25 ppm, or ranging from 9 ppm to 20 ppm;    -   (t) isophthaldehyde in an amount ranging from 0.25 ppm to 10        ppm, or ranging from 0.5 ppm to-5 ppm, or ranging from 0.75 ppm        to 2 ppm; and optionally-   (4) at least one, or at least two, or at least three, or at least    four, or at least five or at least six, or at least seven, or all of    the following:    -   (a) terephthalic acid in an amount of at least 1 ppm, or ranging        from 1 ppm to 5000 ppm, or ranging from 5 ppm to 2500 ppm, or        ranging from 10 ppm to 2000 ppm, or ranging from 15 ppm to 1000        ppm, or ranging from 20 ppm to 500 ppm;    -   (b) phthalic acid in an amount of at least 1 ppm, or ranging        from 1 ppm to 3000 ppm, or ranging from 2 ppm to 2000 ppm, or        ranging from 3 ppm to 1000 ppm, or ranging from 4 ppm to 500        ppm;    -   (c) benzene-tricarboxylic acid isomers in an amount of at least        1 ppm, or ranging from 1 ppm to 3000 ppm, or ranging from 5 ppm        to 2000 ppm, or ranging from 10 ppm to 1000 ppm, or ranging from        20 ppm to 500 ppm;    -   (d) benzoic acid in an amount of at least 1 ppm, or ranging from        1 ppm to 3000 ppm, or ranging from 5 ppm to 2000 ppm, or ranging        from 10 ppm to 1000 ppm, or ranging from 20 ppm to 500 ppm;    -   (e) 3-hydroxybenzoic acid in an amount of at least 1 ppm, or        ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to 400 ppm,        or ranging from 10 ppm to 200 ppm;    -   (f) 3-hydroxymethylbenzoic acid in an amount of at least 1 ppm,        or ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to 400        ppm, or ranging from 10 ppm to 200 ppm;    -   (g) 3,3′-dicarboxybiphenyl in an amount of at least 1 ppm, or        ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to 400 ppm,        or ranging from 10 ppm to 200 ppm;    -   (h) dicarboxyanthraquinone isomers in an amount of at least 0.1        ppm, or ranging from 0.1 ppm to 5 ppm, or ranging from 0.2 ppm        to 4 ppm, or ranging from 0.3 ppm to 3 ppm;        -   wherein the compound or compounds selected in (4) are            different than the compound or compounds selected in (3).

II. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) m-toluic acid (m-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) m-toluic acid (m-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 3-CBA and m-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or at least three, or at least four, or at least    five, or at least six, or all of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) 3,3′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (e) 3-hydroxybenzoic acid ranging from 3 ppm to 200 ppm, or        ranging from 5 ppm to 175 ppm, or ranging from 20 ppm to 150        ppm, or ranging from 3 ppm, or 5 ppm or 20 ppm to 150 ppm, or        175 ppm, or 200 ppm, or 500 ppm, or 1000 ppm;    -   (f) 3-hydroxymethylbenzoic acid in an amount of at least 40 ppm,        or at least 80 ppm, or at least 100 ppm, or ranging from 40 ppm        to 200 ppm, or ranging from 80 ppm to 180, or ranging from 100        ppm to 160 ppm, or ranging from 40 ppm, or 80 ppm, or 100 ppm to        500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (g) benzoic acid ranging from 60 ppm to 500 ppm, or ranging from        75 ppm to 400 ppm, or ranging from 100 ppm to 300 ppm, or        ranging from 60 ppm, or 75 ppm, or 100 ppm to 300 ppm, or 500        ppm, or 1000 ppm.

III. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) m-toluic acid (m-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) m-toluic acid (m-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 3-CBA and m-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or at least three, or at least four, or all of the    following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) 3,3′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (e) benzoic acid ranging from 60 ppm to 500 ppm, or ranging from        75 ppm to 400 ppm, or ranging from 100 ppm to 300 ppm, or        ranging from 60 ppm, or 75 ppm, or 100 ppm to 300 ppm, or 500        ppm, or 1000 ppm.

IV. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) m-toluic acid (m-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) m-toluic acid (m-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 3-CBA and m-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or at least three, or all of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt % or less        than 49 wt %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm,        or 0.5 wt % or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) 3,3′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;

V. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) m-toluic acid (m-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) m-toluic acid (m-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 3-CBA and m-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two or all of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) 3,3′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

VI. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) m-toluic acid (m-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) m-toluic acid (m-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 3-CBA and m-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt % or less        than 49 wt %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm,        or 0.5 wt % or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;

VII. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) m-toluic acid (m-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) m-toluic acid (m-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 3-CBA and m-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) 3,3′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

VIII. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight;-   and-   (2) (a) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) m-toluic acid (m-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) m-toluic acid (m-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 3-CBA and m-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (b) 3,3′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

IX. In another embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) isophthalic acid in an amount greater than 50 percent by weight,    or greater than 60 percent by weight, or greater than 70 percent by    weight, or greater than 80 percent by weight, or greater than 90    percent by weight, or greater than 95 percent by weight, or greater    than 97 percent, or greater than 98 percent, or greater than 98.5    percent, or greater than 99 percent, or greater than 99.5 percent by    weight; and-   (2) 3-carboxybenzaldehyde (3-CBA) in an amount ranging from 1 ppm to    500 ppm, and-   (3) all of the following:    -   (a) terephthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) benzene-tricarboxylic acid isomers ranging from 140 ppm to        1000 ppm, or ranging from 175 ppm to 750 ppm, or ranging from        200 ppm to 500 ppm, or ranging from 150 ppm, or 175 ppm, or 200        ppm to 500 ppm, or 750 ppm, or 1000 ppm;    -   (c) 3,3′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;        Terephthalic Acid Compositions

I. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight;-   and-   (2) (a) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 4-CBA and p-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least one, or at least two, or at least three, or at least    four, or at least five, or at least six, or at least seven, or at    least eight, or at least nine, or at least ten, or at least eleven,    or at least twelve, or at least thirteen, or at least fourteen, or    at least fifteen, or at least sixteen, or at least seventeen, or at    least eighteen, or at least nineteen, or all of the following:    -   (a) isophthalic acid in an amount of at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm    -   (b) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm;    -   (c) trimellitic acid in an amount of at least 140 ppm, or        ranging from 140 ppm to 1000 ppm, or ranging from 175 ppm to 750        ppm, or ranging from 200 ppm to 500 ppm;    -   (d) benzoic acid in an amount of at least 50 ppm, or at least 75        ppm, or at least 100 ppm; or ranging from 50 ppm to 500 ppm, or        ranging from 75 ppm to 400 ppm, or ranging from 100 ppm to 300        ppm;    -   (e) 4-hydroxybenzoic acid in an amount of at least 3 ppm, at        least 5 ppm, or at least 20 ppm, or ranging from 3 ppm to 200        ppm, or ranging from 5 ppm to 175 ppm, or ranging from 20 ppm to        150 ppm;    -   (f) 4-hydroxymethylbenzoic acid in an amount of at least 40 ppm,        or at least 80 ppm, or at least 100 ppm, or ranging from 40 ppm        to 200 ppm, or ranging from 80 ppm to 180, or ranging from 100        ppm to 160 ppm;    -   (g) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm;    -   (h) 2,6-dicarboxyanthraquinone in an amount less than 1 ppm, or        less than 0.5 ppm, or less than 0.4 ppm, or less than 0.35 ppm;    -   (i) 4,4′-dicarboxystilbene in an amount greater than 7 ppm; or        greater than 10 ppm;    -   (j) 2,5,4′-tricarboxybiphenyl in an amount ranging from 8 ppm to        100 ppm, or ranging from 9 ppm to 50 ppm, or ranging from 10 ppm        to 25 ppm;    -   (k) 2,5,4′-tricarboxybenzophenone in an amount ranging from 5        ppm to 100 ppm, or ranging from 6 ppm to 75 ppm, or ranging from        7 ppm to 60 ppm;    -   (l) 4,4′-dicarboxybenzophenone in an amount ranging from 10 ppm        to 150 ppm, or ranging from 12 ppm to 100 ppm, or ranging from        15 ppm to 75 ppm;    -   (m) 4,4′-dicarboxybenzil in an amount ranging from 1 ppm to 30        ppm, or ranging from 2 ppm to 20 ppm, or ranging from 3 ppm to        10 ppm;    -   (n) form-acet-hydroxybenzoic acid in an amount ranging from 1        ppm to 20 ppm, or ranging from 2 ppm to 15 ppm, or ranging from        3 ppm to 10 ppm;    -   (o) acet-hydroxymethylbenzoic acid in an amount ranging from 1        ppm to 30 ppm, or ranging from 2 ppm to 20 ppm, or ranging from        3 ppm to 15 ppm;    -   (p) a-bromo-p-toluic acid in an amount ranging from 1 ppm to 100        ppm, or ranging from 2 ppm to 50 ppm, or ranging from 5 ppm to        25 ppm;    -   (q) bromo-benzoic acid in an amount ranging from 5 ppm to 50        ppm, or ranging from 10 ppm to 40 ppm, or ranging from 15 ppm to        35 ppm;    -   (r) bromo-acetic acid in an amount ranging from 1 ppm to 10 ppm;    -   (s) p-tolualdehye in an amount ranging from 7 ppm to 50 ppm, or        ranging from 8 ppm to 25 ppm, or ranging from 9 ppm to 20 ppm;    -   (t) terephthaldehyde in an amount ranging from 0.25 ppm to 10        ppm, or ranging from 0.5 ppm to-5 ppm, or ranging from 0.75 ppm        to 2 ppm; and optionally,-   (4) at least one, or at least two, or at least three, or at least    four, or at least five or at least six, or at least seven, or all of    the following:    -   (a) isophthalic acid in an amount of at least 1 ppm, or ranging        from 1 ppm to 5000 ppm, or ranging from 5 ppm to 2500 ppm, or        ranging from 10 ppm to 2000 ppm, or ranging from 15 ppm to 1000        ppm, or ranging from 20 ppm to 500 ppm;    -   (b) phthalic acid in an amount of at least 1 ppm, or ranging        from 1 ppm to 3000 ppm, or ranging from 2 ppm to 2000 ppm, or        ranging from 3 ppm to 1000 ppm, or ranging from 4 ppm to 500        ppm;    -   (c) trimellitic acid in an amount of at least 1 ppm, or ranging        from 1 ppm to 3000 ppm, or ranging from 5 ppm to 2000 ppm, or        ranging from 10 ppm to 1000 ppm, or ranging from 20 ppm to 500        ppm;    -   (d) benzoic acid in an amount of at least 1 ppm, or ranging from        1 ppm to 3000 ppm, or ranging from 5 ppm to 2000 ppm, or ranging        from 10 ppm to 1000 ppm, or ranging from 20 ppm to 500 ppm;    -   (e) 4-hydroxybenzoic acid in an amount of at least 1 ppm, or        ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to 400 ppm,        or ranging from 10 ppm to 200 ppm;    -   (f) 4-hydroxymethylbenzoic acid in an amount of at least 1 ppm,        or ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to 400        ppm, or ranging from 10 ppm to 200 ppm;    -   (g) 4,4′-dicarboxybiphenyl in an amount of at least 1 ppm, or        ranging from 1 ppm to 500 ppm, or ranging from 5 ppm to 400 ppm,        or ranging from 10 ppm to 200 ppm;    -   (h) 2,6-dicarboxyanthraquinone in an amount of at least 0.1 ppm,        or ranging from 0.1 ppm to 5 ppm, or ranging from 0.2 ppm to 4        ppm, or ranging from 0.3 ppm to 3 ppm;        -   wherein the compound or compounds selected in (4) are            different than the compound or compounds selected in (3).

II. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight;-   and-   (2) (a) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 4-CBA and p-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or at least three, or at least four, or at least    five, or at least six, or all of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) trimellitic acid ranging from 140 ppm to 1000 ppm, or        ranging from 175 ppm to 750 ppm, or ranging from 200 ppm to 500        ppm, or ranging from 150 ppm, or 175 ppm, or 200 ppm to 500 ppm,        or 750 ppm, or 1000 ppm;    -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (e) 4-hydroxybenzoic acid ranging from 3 ppm to 200 ppm, or        ranging from 5 ppm to 175 ppm, or ranging from 20 ppm to 150        ppm, or ranging from 3 ppm, or 5 ppm or 20 ppm to 150 ppm, or        175 ppm, or 200 ppm, or 500 ppm, or 1000 ppm;    -   (f) 4-hydroxymethylbenzoic acid in an amount of at least 40 ppm,        or at least 80 ppm, or at least 100 ppm, or ranging from 40 ppm        to 200 ppm, or ranging from 80 ppm to 180, or ranging from 100        ppm to 160 ppm, or ranging from 40 ppm, or 80 ppm, or 100 ppm to        500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (g) benzoic acid ranging from 60 ppm to 500 ppm, or ranging from        75 ppm to 400 ppm, or ranging from 100 ppm to 300 ppm, or        ranging from 60 ppm, or 75 ppm, or 100 ppm to 300 ppm, or 500        ppm, or 1000 ppm.

III. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight;-   and-   (2) (a) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 4-CBA and p-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or at least three, or at least four, or all of the    following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) trimellitic acid ranging from 140 ppm to 1000 ppm, or        ranging from 175 ppm to 750 ppm, or ranging from 200 ppm to 500        ppm, or ranging from 150 ppm, or 175 ppm, or 200 ppm to 500 ppm,        or 750 ppm, or 1000 ppm;    -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;    -   (e) benzoic acid ranging from 60 ppm to 500 ppm, or ranging from        75 ppm to 400 ppm, or ranging from 100 ppm to 300 ppm, or        ranging from 60 ppm, or 75 ppm, or 100 ppm to 300 ppm, or 500        ppm, or 1000 ppm.

IV. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight;-   and-   (2) (a) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 4-CBA and p-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two, or at least three, or all of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) trimellitic acid ranging from 140 ppm to 1000 ppm, or        ranging from 175 ppm to 750 ppm, or ranging from 200 ppm to 500        ppm, or ranging from 150 ppm, or 175 ppm, or 200 ppm to 500 ppm,        or 750 ppm, or 1000 ppm;    -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;    -   (d) phthalic acid in an amount of at least 20 ppm, or at least        50 ppm, or at least 100 ppm, or ranging from 20 ppm to 1000 ppm,        or ranging from 50 ppm to 750 ppm, or ranging from 100 ppm to        500 ppm, or ranging from 20 ppm, 50 ppm, 100 ppm to 500 ppm, or        750 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2        wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %,        or ranging from 500 ppm, or 750 ppm, or 1000 ppm to 2000 ppm, or        0.5 wt %, or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt        %, or 25 wt %, or 49 wt %;

V. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight;-   and-   (2) (a) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 4-CBA and p-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) at least two or all of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) trimellitic acid ranging from 140 ppm to 1000 ppm, or        ranging from 175 ppm to 750 ppm, or ranging from 200 ppm to 500        ppm, or ranging from 150 ppm, or 175 ppm, or 200 ppm to 500 ppm,        or 750 ppm, or 1000 ppm;    -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

VI. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight;-   and-   (2) (a) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 4-CBA and p-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) trimellitic acid ranging from 140 ppm to 1000 ppm, or        ranging from 175 ppm to 750 ppm, or ranging from 200 ppm to 500        ppm, or ranging from 150 ppm, or 175 ppm, or 200 ppm to 500 ppm,        or 750 ppm, or 1000 ppm;

VII. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight;-   and-   (2) (a) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 4-CBA and p-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

VIII. In an embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight;-   and-   (2) (a) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1    ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1    ppm to 250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (b) p-toluic acid (p-TA) in an amount ranging from 1 ppm to 1000        ppm, or ranging from 1 ppm to 500 ppm, or ranging from 1 ppm to        250 ppm, or ranging from 1 ppm to 125 ppm; or    -   (c) both of the following:        -   (1) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from            1 ppm to 1000 ppm, or ranging from 1 ppm to 500 ppm, or            ranging from 1 ppm to 250 ppm or ranging from 1 ppm to 125            ppm;        -   (2) p-toluic acid (p-TA) in an amount ranging from 1 ppm to            500 ppm, or ranging from 1 ppm to 250 ppm, or ranging from 1            ppm to 125 ppm;        -   wherein the total concentration of 4-CBA and p-TA ranges            from 1 ppm to 2000 ppm, 1 ppm to 1000 ppm, or from 1 ppm to            500 ppm, or from 1 ppm to 250 ppm, or from 1 ppm to 125 ppm;-   and-   (3) both of the following:    -   (a) trimellitic acid ranging from 140 ppm to 1000 ppm, or        ranging from 175 ppm to 750 ppm, or ranging from 200 ppm to 500        ppm, or ranging from 150 ppm, or 175 ppm, or 200 ppm to 500 ppm,        or 750 ppm, or 1000 ppm;    -   (b) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

IX. In another embodiment of the invention, the dried carboxylic acidcomposition 280 comprises:

-   (1) terephthalic acid in an amount greater than 50 percent by    weight, or greater than 60 percent by weight, or greater than 70    percent by weight, or greater than 80 percent by weight, or greater    than 90 percent by weight, or greater than 95 percent by weight, or    greater than 97 percent, or greater than 98 percent, or greater than    98.5 percent, or greater than 99 percent, or greater than 99.5    percent by weight; and-   (2) 4-carboxybenzaldehyde (4-CBA) in an amount ranging from 1 ppm to    500 ppm, and-   (3) all of the following:    -   (a) isophthalic acid in an amount at least 50 ppm, or ranging        from 50 ppm to 2000 ppm, or ranging from 75 ppm to 1500 ppm, or        ranging from 100 ppm to 1000 ppm, or ranging from 150 ppm to 500        ppm, or ranging from 50 ppm, or 75 ppm, or 100 ppm, or 150 ppm        to 500 ppm, or 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or        2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt        %, or ranging from 500 ppm, or 1000 ppm to 2000 ppm, or 0.5 wt %        or 1 wt %, or 2 wt %, or 3 wt %, or 5 wt %, or 10 wt %, or 25 wt        %, or 49 wt %;    -   (b) trimellitic acid ranging from 140 ppm to 1000 ppm, or        ranging from 175 ppm to 750 ppm, or ranging from 200 ppm to 500        ppm, or ranging from 150 ppm, or 175 ppm, or 200 ppm to 500 ppm,        or 750 ppm, or 1000 ppm;    -   (c) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to        150 ppm, or ranging from 25 ppm to 100 ppm, or ranging from 25        ppm to 75 ppm, or ranging from 200 ppm, or 300 ppm, or 500 ppm        to 1000 ppm, or 2000 ppm, or 0.5 wt %, or 1 wt %, or 2 wt %, or        3 wt %, or 5 wt %, or 10 wt %, or 25 wt %, or 49 wt %;

In another embodiment of this invention, all the compositions of thedried carboxylic acid composition 280 previously stated further comprisea catalyst composition of less than 1000 ppm, or 500 ppm, or 250 ppm, or100 ppm. Other ranges are less than 85 ppm, and less than 50 ppm. Yetanother range is less than 25 ppm, or less than 15 ppm, or less than 10ppm or less than 5 ppm. In another embodiment of the invention, thecatalyst comprises cobalt and manganese. In another embodiment of theinvention, the catalyst comprises cobalt.

All concentrations throughout the disclosure and claims are on a drysolids basis. The physical form of the TPA product can be a dry solid,wet cake, paste, or slurry. For the sake of consistency, any liquidpresent in the TPA product is ignored when describing its composition.The composition will be expressed as a weight percent or ppmw (part permillion by weight) on a dry solids basis which assumes there is nomoisture in the product. For example, 500 ppmw of p-toluic acid in a TPAproduct means there are 500 grams of p-toluic acid for every 1,000,000grams of non-liquid mass in the product regardless of the actualphysical form of the product. All measurements expressed in ppm are ppmby weight. Therefore, ppm is equivalent to ppmw throughout thedisclosure.

In another embodiment of this invention, all the compositions previouslystated are an average composition over a continuous period during steadystate operation. In yet another embodiment of the invention, thecompositions previously disclosed are the time average compositionsobtained over a 7 day period, or 14 day period, or 30 day period duringcontinuous operation. In another embodiment of the invention, thecompositions previously disclosed could include any sample taken from a1 metric ton lot (1,000 kg) or larger. In another embodiment of theinvention, the compositions previously disclosed could include anysample in a shipping container, or a shipping container containing atleast 500 kg of the disclosed compositions.

In an embodiment of the invention, the compositions of matter we havespecified will be utilized to make PET which could be subsequently usedin producing coatings, resins, fibers, film, sheet, containers, or otherformed articles.

In an embodiment of the invention, the compositions previouslydisclosed, can have functionalities in PET polymerization ranging fromzero through at least three. Functional groups for polycondensationpolymerization of polyesters and copolyesters, as well as polyamides,copolyamides, and other co-polycondensation polymers comprise reactivecarboxyl and reactive hydroxyl groups. The following discussion willfocus on the impact of various impurities or oxidation by-products onthe manufacture and properties of poly(ethylene terephthalate) (PET) asan example.

Zero-functional impurities are either removed via purge processes in PETmanufacture or end up as diluting species in the PET. Mono- andtri-functional species affect the rate of polymerization, possibly bothin melt-phase and solid-stating, but usually more so in solid-statingdue to the difficulty of obtaining high molecular weight especially withmonofunctional, chain-terminating species present. Depending on theconcentrations, mono- and tri-functional species also can affect the PETproduct properties via changing the PET polydispersity of molecularweight.

For example, p-toluic acid (p-TA) is an impurity which is monofunctionalin PET polymerization with PET process polymerization catalysts. Incontrast, 4-carboxybenzaldehyde (4-CBA) is monofunctional when used withan Sb (antimony) catalyst in PET polymerization, but can be di- ortri-functional when used with a Ti (titanium) catalyst in PETpolymerization, due to the conversion of the aldehyde group to ahemi-acetal or an acetal. Trimellitic acid (1,2,4-benzene tricarboxylicacid, or TMA) is a tri-functional impurity. To a first approximation,mono- and tri-functional impurities have offsetting effects on PETpolymerization. That is, increased amounts of mono-functionalimpurities, such as p-toluic acid, benzoic acid, monocarboxyfluorenones,bromo-benzoic acid, bromo-acetic acid, and 4-CBA (with Sb catalyst), canbe compensated for via increased concentration of tri- or greaterfunctional impurities, such as trimellitic acid,2,5,4′-tricarboxybiphenyl, 2,5,4′-tricarboxybenzophenone, and 4-CBA(with Ti catalyst). Molar concentrations must be used and notweight-based concentrations when comparing the polymerization effects ofimpurities with functionality other than two, as well as the relativereactivity of reacting groups (primarily carboxyl functionality) whenthe functionality is greater than one. Fortunately, most of theimpurities present in PTA in significant concentrations (more than a fewppmw) are bi-functional and thus have no deleterious effects on PETpolymerization due to their functionality and they have no deleteriouseffects on PET polymer properties due to their low concentration. Inparticular, assuming an Sb-catalyzed PET polymerization process, theneach 1.0 ppmw of TMA will approximately offset approximately 0.60 ppmwbenzoic acid (BA), or 0.65 ppmw p-TA, due to differences in molecularweight. If analytical information is known for PTA impurities, i.e. theconcentrations of the impurities and their functionalities, then anestimate can be made of the relative overall effect on PETpolymerization.

Note that for IPA instead of TPA, the compounds will be 3-hydroxybenzoicacid, 3-hydroxymethylbenzoic acid, 3,3′-dicarboxybiphenyl,dicarboxyanthraquinone isomers, and 3,3′-dicarboxystilbene, etc.Similarly, for carboxylic acids, the compounds will be hydroxybenzoicacid isomers, hydroxymethylbenzoic acid isomers, dicarboxybiphenylisomers, dicarboxyanthraquinone isomers, and dicarboxystilbene isomers,etc.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have a total monofunctionalcompound(s) concentration less than 0.5 mole %, or less than 0.25 mole%, or less than 0.1 mole %, or less than 0.05 mole %, or less than 0.025mole %, or less than 0.01 mole %, or less than 0.005 mole %.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have a total monofunctionalcompound(s) concentration less than 5000 ppm, or less than 2500 ppm, orless than 1000 ppm, or less than 500 ppm, or less than 250 ppm, or lessthan 100 ppm, or less than 50 ppm.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have a total tri-functionaland greater-than-tri-functional compound(s) concentration less than 0.5mole %, or less than 0.25 mole %, or less than 0.1 mole %, or less than0.05 mole %, or less than 0.025 mole %, or less than 0.01 mole %, orless than 0.005 mole %.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have a total tri-functionaland greater-than-tri-functional compound(s) concentration less than 5000ppm, or less than 2500 ppm, or less than 1000 ppm, or less than 500 ppm,or less than 250 ppm, or less than 100 ppm, or less than 50 ppm.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have a total zero-functionalcompound(s) concentration less than 0.5 mole %, or less than 0.25 mole%, or less than 0.1 mole %, or less than 0.05 mole %, or less than 0.025mole %, or less than 0.01 mole %, or less than 0.005 mole %.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have a total zero-functionalcompound(s) concentration less than 5000 ppm, or less than 2500 ppm, orless than 1000 ppm, or less than 500 ppm, or less than 250 ppm, or lessthan 100 ppm, or less than 50 ppm.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have an averagefunctionality, not including zero functionality species, of at least1.995 or greater, or at least 1.996 or greater, or at least 1.997 orgreater, or at least 1.998 or greater, or at least 1.999 or greater, orat least 1.9995 or greater, or at least 1.9999 or greater.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have an averagefunctionality, not including zero functionality species, of between1.995, or 1.996, or 1.997, or 1.998, or 1.999, or 1.9995, or 1.9999 and2.0000, or 2.0001, or 2.0005, or 2.001, or 2.002 or 2.003, or 2.004, or2.005.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have an average carboxylfunctionality, not including species with zero carboxyl functionality,of at least 1.995 or greater, or at least 1.996 or greater, or at least1.997 or greater, or at least 1.998 or greater, or at least 1.999 orgreater, or at least 1.9995 or greater, or at least 1.9999 or greater.

In another embodiment of the invention, the previously disclosedcarboxylic acid compositions comprising terephthalic or isophthalic acidor any di-functional carboxylic acid would have an average carboxylfunctionality, not including species with zero carboxyl functionality,of between 1.995, or 1.996, or 1.997, or 1.998, or 1.999, or 1.9995, or1.9999 and 2.0000, or 2.0001, or 2.0005, or 2.001, or 2.002 or 2.003, or2.004, or 2.005.

In another embodiment of the invention, a process for producing anenriched composition 240 is provided as shown in FIGS. 20A and 20B. Inthis embodiment, as shown in FIGS. 20 a&b, the catalyst removal zone 180is optional and the enrichment zone 210 is required. All of the zones inFIGS. 20 A&B have been previously been described in this disclosure. Itshould be appreciated that the process zones previously described can beutilized in any other logical order to produce the dried carboxylic acidcomposition 280. It should also be appreciated that when the processzones are reordered that the process conditions may change. It shouldalso be appreciated that the process zones can be used independently.

In another embodiment of this invention, each embodiment can optionallyinclude an additional step comprising decolorizing the carboxylic acidor an esterified carboxylic acid. Preferably the decolorizing isaccomplished by hydrogenation. The decolorizing can occur at anylocation after the primary oxidation zone 20.

The decolorizing of a carboxylic acid slurry or an esterified carboxylicacid can be accomplished by any means known in the art and is notlimited to hydrogenation. However, for example in one embodiment of theinvention, the decolorizing can be accomplished by reacting a carboxylicacid that has undergone esterification treatment, for example withethylene glycol, with molecular hydrogen in the presence of ahydrogenation catalyst in a decolorizing reactor zone to produce adecolorized carboxylic acid solution or a decolorized ester product. Forthe decolorizing reactor zone, there are no special limitations in theform or construction thereof, subject to an arrangement that allowssupply of hydrogen to effect intimate contact of the carboxylic acid orester product with the catalyst in the decolorizing reactor zone.Typically, the hydrogenation catalyst is usually a single Group VIIImetal or combination of Group VIII metals. Preferably, the hydrogenationcatalyst is selected from a group consisting of palladium, ruthenium,rhodium and combination thereof. The decolorizing reactor zone comprisesa hydrogenation reactor that operates at a temperature and pressuresufficient to hydrogenate a portion of the characteristically yellowcompounds to colorless derivatives.

In another embodiment of the invention, instead of utilizing the dryingzone as preciously disclosed, the enriched composition 240 can bedirectly routed to an esterification zone 310 as shown in FIG. 16. Inthis embodiment, the moisture content in the enriched composition 240 ispredominantly water and the weight % of acetic acid in the enrichedcomposition 240 is less than 10%, preferably less than 2%, and mostpreferably less than 0.1%. “Predominantly” as used herein means greaterthan 85% of total moisture mass.

Therefore, instead of drying, in an embodiment of the invention, step(i) comprises adding a diol in conduit 600 to the enriched composition240 in an esterification reactor zone 610 to remove a portion of themoisture via conduit 620 to form a carboxylic acid and diol mixture inthe esterification reactor zone 610. The carboxylic acid and diol reactto form a hydroxyalkyester stream 630. The hydroxyalkyester stream 630comprises a hydroxyalky ester compound.

The diol in conduit 600 is introduced in such a manner as to displacethe moisture as the dominant slurrying liquid. This can be accomplishedby introducing a diol via conduit 600 as a saturated liquid in atemperature range of about 150° C. to about 300° C. Preferably, the diolin conduit 600 is introduced as a saturated or superheated vapor in atemperature range of about 150° C. to about 300° C. in a form withsufficient enthalpy as to evaporate the water to exit via conduit 320.The diol in conduit 600 is selected from the group consisting ofethylene glycol, diethylene glycol, tri-ethylene glycol,1,3-propanediol, 1,2-propanediol, 1,4-butanediol, 1,3-butanediol,cyclohexanedimethanol, neopentyl glycol, other diols useful in makingpolyesters and copolyesters, and mixtures thereof. Preferably, the diolin conduit 600 is ethylene glycol. Alternatively, an external heatsource can be used to introduce sufficient enthalpy to vaporize thewater, which exits via conduit 620. The hydroxalkyl ester stream mixtureexits via conduit stream 630.

The esterification reactor zone 610 operates at a temperature of about240° C. higher. Preferably the esterification reactor zone 610 operatesin a temperature range of about 260° C. to about 280° C. Theesterification reactor zone 610 operates at a pressure of about 40 psiato about 100 psia so as to effect esterification of the terephthalicacid and diol mixture to produce a hydroxyethyl ester of terephthalicacid.

In another embodiment of the invention, instead of utilizing the dryingzone as preciously disclosed, the enriched composition 240 can bedirectly routed to a liquid exchange zone 500 as shown in FIG. 17. Inthis embodiment, the moisture content in the enriched composition 240has a significant amount of solvent. “Significant amount” as used hereinmeans greater than 1%, or greater than 2%, or greater than 5% or greaterthan 10% or greater than 15%.

The enriched composition 240 is subjected to a wash or “rinsing” withexchange solvent in the liquid exchange zone 500, wherein a portion ofthe initial solvent is replaced with exchange solvent to form anexchange solvent enriched composition 246. The exchange solventcomprises water, methanol, ethylene glycol, and any diol or monomercompatible with polyester or copolyester manufacturing process. Theexchange solvent enriched composition 246, is preferably in the range of0.5-30% by weight moisture, more preferably in the range of about 1-20%by weight moisture, and most preferably in the range of 1-5% by weightmoisture. The residual moisture of the exchange solvent enrichedcomposition 206 could contain less than about 2% by weight solvent,another range is less than 5% or less than 10% by weight, or less than20%.

In an embodiment of the invention, exchange solvent is introduced intothe liquid exchange zone 500. The exchange solvent is preferablyintroduced on a continuous basis. There are no limitations on thetemperature or pressure of the exchange solvent including the use ofvaporized water, steam, or a combination of water and steam as wash.

The liquid exchange zone 500 comprises at least one solid liquidseparation device. The solid liquid separation device can typically becomprised of, but not limited to, the following types of devices:centrifuges, cyclones, rotary drum filters, belt filters, press filters,etc. The solid liquid separation device can operate within a temperaturerange of from about 5° C. to 195° C. The liquid exchange zone and thecatalyst removal zone can be within the same device, for example in abelt filter. The exchange solvent enriched composition 246 issubsequently sent to an esterification zone 610 which has beenpreviously described.

EXAMPLES

An Embodiment of this invention can be further illustrated by thefollowing examples of preferred embodiments thereof, although it will beunderstood that these examples are included merely for purposes ofillustration and are not intended to limit the scope.

PTA Retention Experiments

The objective of this set of experiments was to determine how theretention of IPA in cooled carboxylic acid composition stream 170 varieswith wash temperature and wash ratio of wash feed stream 175 in thecatalyst removal zone 180. All experiments utilized a bench scalePannevis vacuum filter apparatus. Cooled carboxylic acid compositionstream 170 was prepared by taking a crystallized slurry compositionstream 160 slurry at 30 weight percent solids and boiling away solventuntil reaching 50% solids. The slurry was then cooled to 30° C. togenerate a cooled carboxylic acid composition stream 170 and charged tothe vacuum filter, and then washed with a wash feed stream 175. Both thewash ratio and the wash temperature were varied in the experiment. Awash ratio of 1 and 0.5 was used. A wash temperature of 90° C. and 10°C. was used. The wash was 90% acetic acid and 10% water. The time afteradding the wash till the dry top of the cake was observed is called theDry Top Time and was recorded. Samples of the post catalyst removalcomposition 200 were analyzed for ppm wt IPA.

Experiment 1 (No Wash)

700.10 g of crystallized slurry composition stream 160 were charged to astainless steel beaker. The slurry was heated until the weight of theslurry was reduced to 420 gms. The slurry was cooled rapidly to 30° C.using wet ice generating a cooled carboxylic acid composition stream170. The cooled carboxylic acid composition stream 170 was fed to abench scale Pannevis vacuum filter. After feeding the cooled carboxylicacid composition stream 170 to the vacuum filter 16.5 grams of thecooled carboxylic acid composition stream 170 remained in the steelbeaker. The actual mass of the cooled carboxylic acid composition stream170 to the filter was 403.5 grams, (420 grams-16.5 grams). The weight ofthe wet cake pre catalyst removal composition stream was 266.38 grams.The % solids of the wet cake was 94.2%. Samples from the wet cake weresubmitted to analytical for IPA analyses.

Experiment 2 (Wash Ratio 0.5, Wash Temperature 90° C.)

700.04 g of crystallized slurry composition stream 160 was charged to astainless steel beaker. The slurry was heated until the weight of theslurry was reduced to 420.73 gms. The slurry was cooled rapidly to 30°C. using wet ice generating a cooled carboxylic acid composition Stream170. The cooled carboxylic acid composition stream 170 was fed to abench scale Pannevis vacuum filter. After feeding the cooled carboxylicacid composition stream 170 to the vacuum filter 16.5 grams of thecooled carboxylic acid composition stream 170 remained in the stainlesssteel beaker. The actual mass of the cooled carboxylic acid compositionstream 170 to the filter was 405.94 grams, (420.73 grams-14.79 grams).The filter cake was washed with 100.18 gms of 90° C. acetic acid/watersolution wash fed stream 175. The weight of the wet cake post catalystremoval composition stream 200 was 232.83 grams. The % solids of the wetcake post catalyst composition stream 200 was 99.2%. Samples from thewet cake were submitted to analytical for IPA analyses.

Experiment 3 (Wash Ratio 1.0, Wash Temperature 90° C.)

700.39 g of crystallized slurry composition stream 160 were charged to astainless steel beaker. The slurry was heated until the weight of theslurry was reduced to 420.25 gms. The slurry was cooled rapidly to 30°C. using wet ice generating a cooled carboxylic acid composition Stream170. The cooled carboxylic acid composition stream 170 was fed to abench scale Pannevis vacuum filter. After feeding stream 170 to thevacuum filter, 12.69 grams of Stream 170 remained in the stainless steelbeaker. The actual mass of stream 170 to the filter was 407.56 grams,(420.25 grams-12.69 grams). The filter cake was washed with 200.14 gmsof 90 C acetic acid/water solution wash fed stream 175. The weight ofthe wet cake post catalyst removal composition stream 200 was 226.61grams. The % solids of the wet cake post catalyst composition stream 200was 95.4%. Samples from the post catalyst removal composition 200 weresubmitted to analytical for IPA analyses.

Experiment 4 (Wash Ratio 0.5, Wash Temperature 10° C.)

700.3 g of crystallized slurry composition stream 160 were charged to astainless steel beaker. The slurry was heated until the weight of theslurry was reduced to 420.3 gms. The slurry was cooled rapidly to 30° C.using wet ice generating a cooled carboxylic acid composition stream170. Stream 170 was fed to a bench scale Pannevis vacuum filter. Afterfeeding stream 170 to the vacuum filter, 15.29 grams of stream 170remained in the stainless steel beaker. The actual mass of Stream 170 tothe filter was 405.01 grams, (420.3 grams-15.29 grams). The filter cakewas washed with 100.37 grams of 10° C. acetic acid/water solution washfed stream 175. The weight of the wet cake post catalyst removalcomposition stream 200 was 248.84 grams. The % solids of the wet cakepost catalyst composition stream 200 was 90.75%. Samples from the postcatalyst removal composition were submitted to analytical for IPAanalyses.

Experiment 5 (Wash Ratio 1.0, Wash Temperature 10° C.)

700.44 g of crystallized slurry composition stream 160 were charged to astainless steel beaker. The slurry was heated until the weight of theslurry was reduced to 420.35 gms. The slurry was cooled rapidly to 30°C. using wet ice generating a cooled carboxylic acid composition Stream170. The cooled carboxylic acid composition stream 170 was fed to abench scale Pannevis vacuum filter. After feeding stream 170 to thevacuum filter, 9.3 grams of stream 170 remained in the stainless steelbeaker. The actual mass of stream 170 to the filter was 411.05 grams,(420.35 grams-9.3 grams). The filter cake was washed with 200.06 gramsof 10° C. acetic acid/water solution wash fed stream 175. The weight ofthe wet cake post catalyst removal composition stream 200 was 225.06grams. The % solids of the wet cake post catalyst composition Stream 200was 89.55%. Samples from the post catalyst removal composition 200 weresubmitted to analytical for IPA analyses.

Results

Experiment Wash Temp. Wash Ratio IPA (ppmw) Dry Top (sec) 1 no wash nowash 3249 Na 2 90° C. 0.5 146 5 3 90° C. 1.0 25 10 4 10° C. 0.5 39 9 510° C. 1.0 20 17

It is clear that retention of IPA varies with wash temperature and washratio allowing the control of the IPA content in the post catalystremoval composition stream 200. The range of IPA content in stream 200in the experiments above varied from 146 ppm to 20 ppm depending uponthe amount and temperature of wash. Retention of select oxidationby-products can be controlled by the temperature, composition, andamount of wash feed Stream 175 applied in the catalyst removal zone 180.This data illustrates oxidation by-product retention in a catalystremoval zone utilizing IPA as an example. IPA is consideredrepresentative such that other oxidation by-products can exhibit similarretention behavior under specific wash temperature and wash ratiocombinations.

PTA Enrichment with Isophthalic Acid

The objective of this experiment was to demonstrate terephthalic acidenrichment.

In experiment 1, cooled carboxylic acid composition stream 170 slurrywas charged to a bench scale Pannevis vacuum filter apparatus and theresulting post catalyst removal composition 200 was analyzed for IPAcontent.

In experiments 2 and 3, cooled carboxylic acid composition Stream 170slurry was charged to a bench scale Pannevis vacuum filter and theresulting wet cake was washed with wash feed stream 175 and the postcatalyst removal composition stream 200 was analyzed for IPA content.The wash feed stream 175 contained 90% acetic acid and 10% water byweight.

In experiments 4 and 5 the cooled carboxylic acid composition stream 170slurry was charged to a bench scale Pannevis vacuum filter and theresulting wet cake was washed with hot wash feed Stream 175. Theresulting post catalyst removal composition stream 200 wet cake was thenwashed with an enrichment feed stream 220 and resulting enrichedcarboxylic acid composition was analyzed for IPA content. Both thecatalyst removal Zone 180 and the enrichment Zone 210 were accomplishedwith the bench scale Pannevis vacuum filter apparatus.

The enrichment feed Stream 220 used in experiments 4 and 5 were preparedin this matter. Acetic acid was heated to 80° C. and enough IPA wasadded until the IPA would no longer go into solution.

Experiment 1 (No Cake Wash, No Enrichment Wash)

401.67 grams of the cooled carboxylic acid stream 170 at 23.9° C. wasfed to the catalyst removal zone 180 which was a bench scale Pannevisvacuum filter. There was no wash feed stream 175. The stream 200 wetcake weight was 145.55 grams and the % solids was 89.4%. A sample of thewet cake was submitted to analytical for IPA analyses.

Experiment 2 (80° C. Cake Wash, No Enrichment Wash)

400.33 grams of the cooled carboxylic acid composition stream 170 slurryat 29.3° C. was fed to the catalyst removal zone 180 which was a benchscale Pannevis vacuum filter. The filter cake was washed with 100.11grams of 80.2° C. wash feed stream 175. The resulting post catalystremoval stream 200 weight was 139.49 g and the % solids was 99.94%.Samples from the post catalyst removal composition 200 were submitted toanalytical for IPA analyses.

Experiment 3 (80 C Cake Wash, No Enrichment Wash)

401.17 grams of the cooled carboxylic acid composition stream 170 at 24°C. was fed to the catalyst removal zone 180 which was a bench scalePannevis vacuum filter. The filter cake was washed with 100.05 grams of80.0° C. wash feed stream 175. The resulting post catalyst removalcomposition weight was 124.07 grams and the % solids was 99.95%. Asample of the post catalyst removal composition 200 was submitted toanalytical for IPA analyses.

Experiment 4 (80° C. Cake Wash, 80 C Enrichment Wash)

400.45 grams of the cooled carboxylic acid composition stream 170 at24.3° C. was fed to the catalyst removal Zone 180 which was a benchscale Pannevis vacuum filter. The filter cake was washed with 100.11grams of 80.1 C wash feed stream 175. The wet cake was then enrichedwith 100.52 gms of 80.2° C. enrichment feed stream 220. The resultingenriched carboxylic acid composition stream 240 weight was 131.33 gramsand the % solids were 99.9%. Samples from enriched carboxylic acidcomposition stream 240 was submitted to analytical for IPA analyses.

Experiment 5 (80 C Cake Wash, 80° C. Enrichment Wash)

400.55 grams of the cooled carboxylic acid composition stream 170 at24.4° C. was fed to the catalyst removal zone 180 which was a benchscale Pannevis vacuum filter. The filter cake was washed with 100.28grams of 80.2° C. wash feed stream 175. The wet cake was then enrichedwith 100.54 gms of 80.0° C. enrichment feed stream 220. The resultingenriched carboxylic acid composition stream 240 weight was 144.54 gramsand the % solids were 98.8%. Samples from enriched carboxylic acidcomposition stream 240 were submitted to analytical for IPA analyses.

Results

Experiment # Ppm IPA 1 2199 2 1087 3 804 4 4676 5 5535

In experiment 1 the wet cake is not washed resulting in a concentrationof 2199 ppm IPA. In experiments 2 and 3, the wet cake is wash withstream 175 producing a post catalyst composition 200 with an average IPAconcentration of about 900 ppm. In experiments 4 and 5 the post catalystcomposition 200 is enriched with an enrichment stream 220 to produce anenriched carboxylic composition 240 with an average IPA concentration ofabout 5000 ppm. It is clear from this data that IPA was enriched instream 240 to a concentration above that of the post catalystcomposition. This data illustrates oxidation by-product enrichment in anenrichment zone utilizing IPA as an example. IPA is consideredrepresentative of other oxidation by-products in that the retention ofother oxidation by-products in the catalyst removal zone can beinfluenced by the wash conditions, including the wash ratio, washsolvent composition, and wash temperature, as well as the cake thicknessand the particle size distribution which affects the cake porosity.

1. A terephthalic acid composition suitable for making PET (polyethyleneterephthalate) polymer comprising: (1) terephthalic acid in an amountgreater than 50 percent by weight; (2) (a) 4-carboxybenzaldehyde in anamount ranging from 1 ppm to 1000 ppm; or (b) p-toluic acid in an amountranging from 1 ppm to 1000 ppm; or both (2) (a) and (2) (b); and (3) atleast one of the following: (a) isophthalic acid in an amount rangingfrom 50 ppm to 49 wt %; (b) trimellitic acid in an amount ranging from140 ppm to 1000 ppm; (c) 4,4′-dicarboxybiphenyl in an amount rangingfrom 25 ppm to 49 wt %; (d) phthalic acid in an amount ranging from 20ppm to 49 wt %; (e) 4-hydroxybenzoic acid in an amount ranging from 3ppm to 1000 ppm; (f) 4-hydroxymethylbenzoic acid in an amount rangingfrom 40 ppm to 49 wt %; and (g) benzoic acid in an amount ranging from 1ppm to 3000 ppm; and wherein said terephthalic acid composition has atotal monofunctional compound(s) concentration less than 0.5 mole %; andwherein said terephthalic acid composition has an average functionality,not including zero functionality species ranging from 1.995 to 2.005 ona mole basis wherein the functional value for any particular molecule insaid terephthalic acid composition is equal to the total number ofreactive carboxyl and reactive hydroxyl groups present in said molecule.2. A terephthalic acid composition according to claim 1 wherein saidisophthalic acid is in an amount ranging from at 50 ppm to 5 wt %.
 3. Aterephthalic acid composition according to claim 2 wherein saidtrimellitic acid is in an amount ranging from 175 ppm to 750 ppm.
 4. Aterephthalic acid composition according to claim 3 wherein said4-hydroxybenzoic acid is in an amount ranging from 20 ppm to 1000 ppm.5. A terephthalic acid composition according to claim 4 wherein said4-hydroxymethylbenzoic acid is in an amount of ranging from 40 ppm to 1wt %.
 6. A terephthalic acid composition according to claim 1 whereinsaid isophthalic acid is in an amount ranging from at 50 ppm to 1 wt %.7. A terephthalic acid composition according to claim 6 wherein saidbenzoic acid is in an amount ranging from 60 ppm to 500 ppm.
 8. Aterephthalic acid composition according to claim 7 wherein saidtrimellitic acid is in an amount ranging from 200 ppm to 500 ppm.
 9. Aterephthalic acid composition according to claim 8 wherein said phthalicacid is in an amount ranging from 20 ppm to 2000 ppm.
 10. A terephthalicacid composition according to claim 9 wherein said 4-hydroxybenzoic acidis in an amount ranging from 150 ppm to 1000 ppm.
 11. A terephthalicacid composition according to claim 10 wherein said4-hydroxymethylbenzoic acid is in an amount ranging from 40 ppm to 0.5wt %.
 12. A terephthalic acid composition according to claim 11 whereinsaid benzoic acid is in an amount ranging from 60 ppm to 300 ppm.
 13. Aterephthalic acid composition suitable for making PET (polyethyleneterephthalate) polymer comprising: (1) terephthalic acid in an amountgreater than 50 percent by weight; (2) (a) 4-carboxybenzaldehyde in anamount ranging from 1 ppm to 1000 ppm; or (b) p-toluic acid in an amountranging from 1 ppm to 1000 ppm; or both (2) (a) and (2) (b); and (3) atleast two of the following: (a) isophthalic acid in an amount rangingfrom ranging from 50 ppm to 49 wt %; (b) trimellitic acid in an amountranging from 140 ppm to 1000 ppm; (c) 4,4′-dicarboxybiphenyl in anamount ranging from 25 ppm to 49 wt %; (d) phthalic acid in an amountranging from 20 ppm to 49 wt %; (e) 4-hydroxybenzoic acid in an amountranging from 3 ppm to 1000 ppm; (f) 4-hydroxymethylbenzoic acid in anamount ranging from 40 ppm to 49 wt %; and (g) benzoic acid in an amountranging from 1 ppm to 3000 ppm; and wherein said terephthalic acidcomposition has a total monofunctional compound(s) concentration lessthan 0.5 mole % and wherein said terephthalic acid composition has anaverage functionality, not including zero functionality species rangingfrom 1.995 to 2.005 on a mole basis wherein the functional value for anyparticular molecule in said terephthalic acid composition is equal tothe total number of reactive carboxyl and reactive hydroxyl groupspresent in said molecule.
 14. A terephthalic acid composition accordingto claim 13 wherein said isophthalic acid is in an amount ranging from50 ppm to 5 wt %.
 15. A terephthalic acid composition according to claim14 wherein said trimellitic acid is in an amount ranging from 175 ppm to750 ppm.
 16. A terephthalic acid composition according to claim 15wherein said phthalic acid is in an amount ranging from 20 ppm to 1 wt%.
 17. A terephthalic acid composition according to claim 16 whereinsaid benzoic acid is in an amount ranging from 60 ppm to 500 ppm.
 18. Aterephthalic acid composition according to claim 13 wherein saidisophthalic acid is in an amount ranging from 50 ppm to 1 wt %.
 19. Aterephthalic acid composition according to claim 18 wherein saidphthalic acid is in an amount ranging from 20 ppm to 2000 ppm.
 20. Aterephthalic acid composition according to claim 19 wherein said4-hydroxybenzoic acid is in an amount ranging from 150 ppm to 1000 ppm.